diff --git a/manage.py b/manage.py
index 52b12342b..c48eab6ab 100755
--- a/manage.py
+++ b/manage.py
@@ -2,8 +2,8 @@
 import os
 import sys
 
-if __name__ == "__main__":
-    os.environ.setdefault("DJANGO_SETTINGS_MODULE", "wcs.settings")
+if __name__ == '__main__':
+    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'wcs.settings')
 
     from django.core.management import execute_from_command_line
 
diff --git a/setup.py b/setup.py
index b8a72a03d..3da2bf8cf 100644
--- a/setup.py
+++ b/setup.py
@@ -171,9 +171,9 @@ cmdclass = {
 setup(
     name='wcs',
     version=get_version(),
-    maintainer="Frederic Peters",
-    maintainer_email="fpeters@entrouvert.com",
-    url="http://wcs.labs.libre-entreprise.org",
+    maintainer='Frederic Peters',
+    maintainer_email='fpeters@entrouvert.com',
+    url='http://wcs.labs.libre-entreprise.org',
     install_requires=[
         'Quixote>=3.0,<3.2',
         'django>=3.2',
diff --git a/tests/admin_pages/test_form.py b/tests/admin_pages/test_form.py
index 32b48178b..33f9a0560 100644
--- a/tests/admin_pages/test_form.py
+++ b/tests/admin_pages/test_form.py
@@ -1996,7 +1996,7 @@ def test_form_edit_field_advanced(pub):
     resp = resp.forms[0].submit('submit')
     assert resp.location == 'http://example.net/backoffice/forms/1/fields/#fieldId_2'
     resp = resp.follow()
-    assert "Are you sure you want to prefill" not in resp.text
+    assert 'Are you sure you want to prefill' not in resp.text
 
 
 def test_form_edit_field_display(pub):
diff --git a/tests/admin_pages/test_workflow.py b/tests/admin_pages/test_workflow.py
index cb7a10c66..aea60e96e 100644
--- a/tests/admin_pages/test_workflow.py
+++ b/tests/admin_pages/test_workflow.py
@@ -600,7 +600,7 @@ def test_workflows_copy_status_item(pub):
     pub.write_cfg()
 
     resp = app.get('/backoffice/workflows/%s/status/%s/' % (workflow.id, st1.id))
-    resp = resp.click(href="items/_commentable/copy")
+    resp = resp.click(href='items/_commentable/copy')
     resp = resp.form.submit('submit')
     assert '<ul><li>Unknown roles: unknown</li></ul>' in resp
 
@@ -1200,12 +1200,12 @@ def test_workflows_edit_email_action(pub):
 
     # attachments without backoffice fields: python expressions
     resp = app.get(item_url)
-    assert "Attachments (templates)" in resp.text
+    assert 'Attachments (templates)' in resp.text
     resp.form['attachments$element0'] = 'form_var_upload_raw'
     resp = resp.form.submit('submit')
     assert resp.location
     resp = app.get(item_url)
-    assert "Attachments (templates)" in resp.text
+    assert 'Attachments (templates)' in resp.text
     assert resp.form['attachments$element0'].value == 'form_var_upload_raw'
     sendmail = Workflow.get(workflow.id).get_status(st1.id).items[0]
     assert sendmail.attachments == ['form_var_upload_raw']
@@ -1220,8 +1220,8 @@ def test_workflows_edit_email_action(pub):
     ]
     workflow.store()
     resp = app.get(item_url)
-    assert "Attachments" in resp.text
-    assert "Attachments (templates)" not in resp.text
+    assert 'Attachments' in resp.text
+    assert 'Attachments (templates)' not in resp.text
     assert resp.form['attachments$element0$choice'].value == '{{form_var_upload_raw}}'
     assert len(resp.form['attachments$element0$choice'].options) == 5
     resp = resp.form.submit('attachments$add_element')  # add one
@@ -1291,7 +1291,7 @@ def test_workflows_edit_email_action(pub):
     workflow.backoffice_fields_formdef.fields = []
     workflow.store()
     resp = app.get(item_url)
-    assert "Attachments (templates)" in resp.text
+    assert 'Attachments (templates)' in resp.text
     resp = resp.form.submit('submit')
     assert resp.location
     sendmail = Workflow.get(workflow.id).get_status(st1.id).items[0]
@@ -2695,21 +2695,21 @@ def test_workflows_global_actions_external_workflow_action(pub):
     assert 'External workflow (not completed)' in resp.text
 
     resp = app.get('/backoffice/workflows/%s/status/%s/items/1/' % (workflow.id, st.id))
-    assert "No workflow with external triggerable global action." in resp.text
+    assert 'No workflow with external triggerable global action.' in resp.text
 
     trigger.identifier = 'test'
     wf.store()
     resp = app.get('/backoffice/workflows/%s/status/%s/items/1/' % (workflow.id, st.id))
 
     resp = resp.forms[0].submit('submit')
-    assert "required field" in resp.text
+    assert 'required field' in resp.text
     resp.forms[0]['slug'] = 'formdef:%s' % formdef.url_name
     assert (
         resp.pyquery('select#form_slug option')[1].attrib['data-goto-url']
         == 'http://example.net/backoffice/forms/1/'
     )
     resp = resp.forms[0].submit('submit')
-    assert "required field" in resp.text
+    assert 'required field' in resp.text
     resp = resp.forms[0].submit('submit')
     resp.forms[0]['trigger_id'] = 'action:%s' % trigger.identifier
     resp = resp.forms[0].submit('submit').follow().follow()
@@ -2767,7 +2767,7 @@ def test_workflows_external_workflow_action_config(pub):
     resp = resp.forms[0].submit('submit')
     assert 'There were errors processing your form.  See below for details.' not in resp
     assert 'This action is configured in two steps. See below for details.' in resp
-    assert "required field" in resp
+    assert 'required field' in resp
     # multiple errors: do as usual
     resp.forms[0]['slug'] = 'formdef:external'
     resp.forms[0]['condition$type'] = 'django'
@@ -2775,7 +2775,7 @@ def test_workflows_external_workflow_action_config(pub):
     resp = resp.forms[0].submit('submit')
     assert 'There were errors processing your form.  See below for details.' in resp
     assert 'This action is configured in two steps. See below for details.' not in resp
-    assert "required field" in resp
+    assert 'required field' in resp
     assert "syntax error: Could not parse the remainder: '{{' from '{{'" in resp
 
 
diff --git a/tests/api/test_carddef.py b/tests/api/test_carddef.py
index 843ed2a44..380244860 100644
--- a/tests/api/test_carddef.py
+++ b/tests/api/test_carddef.py
@@ -1301,7 +1301,7 @@ def test_formdef_submit_structured(pub, local_user):
 
     for post_data in [
         # straight id
-        {'0': '0', "1": '3'},
+        {'0': '0', '1': '3'},
         # varnames
         {'foobar': '0', 'foobar1': '3'},
         # varnames with integer as values
@@ -1318,10 +1318,10 @@ def test_formdef_submit_structured(pub, local_user):
             rsps.get(
                 'http://datasource.com',
                 json={
-                    "data": [
-                        {"id": 0, "text": "zéro", "foo": "bar"},
-                        {"id": 1, "text": "uné", "foo": "bar1"},
-                        {"id": 2, "text": "deux", "foo": "bar2"},
+                    'data': [
+                        {'id': 0, 'text': 'zéro', 'foo': 'bar'},
+                        {'id': 1, 'text': 'uné', 'foo': 'bar1'},
+                        {'id': 2, 'text': 'deux', 'foo': 'bar2'},
                     ]
                 },
             )
@@ -1514,7 +1514,7 @@ def test_cards_filter_function(pub, local_user):
     custom_view.title = 'shared carddef custom view'
     custom_view.formdef = carddef
     custom_view.columns = {'list': [{'id': '0'}]}
-    custom_view.filters = {"filter-user-function": "on", "filter-user-function-value": "_foobar"}
+    custom_view.filters = {'filter-user-function': 'on', 'filter-user-function-value': '_foobar'}
     custom_view.visibility = 'any'
     custom_view.store()
 
diff --git a/tests/api/test_custom_view.py b/tests/api/test_custom_view.py
index 9fd2c06d1..f9da45765 100644
--- a/tests/api/test_custom_view.py
+++ b/tests/api/test_custom_view.py
@@ -188,7 +188,7 @@ def test_api_list_formdata_custom_view(pub, local_user):
     custom_view.title = 'custom view'
     custom_view.formdef = formdef
     custom_view.columns = {'list': [{'id': '0'}]}
-    custom_view.filters = {"filter": "done", "filter-status": "on"}
+    custom_view.filters = {'filter': 'done', 'filter-status': 'on'}
     custom_view.visibility = 'any'
     custom_view.store()
 
@@ -252,7 +252,7 @@ def test_api_ods_formdata_custom_view(pub, local_user):
     custom_view.title = 'custom view'
     custom_view.formdef = formdef
     custom_view.columns = {'list': [{'id': '0'}]}
-    custom_view.filters = {"filter": "done", "filter-status": "on"}
+    custom_view.filters = {'filter': 'done', 'filter-status': 'on'}
     custom_view.visibility = 'any'
     custom_view.store()
 
@@ -306,7 +306,7 @@ def test_api_geojson_formdata_custom_view(pub, local_user):
     custom_view.title = 'custom view'
     custom_view.formdef = formdef
     custom_view.columns = {'list': [{'id': '0'}]}
-    custom_view.filters = {"filter": "done", "filter-status": "on"}
+    custom_view.filters = {'filter': 'done', 'filter-status': 'on'}
     custom_view.visibility = 'any'
     custom_view.store()
 
@@ -355,7 +355,7 @@ def test_api_get_formdata_custom_view(pub, local_user):
     custom_view.title = 'custom view'
     custom_view.formdef = formdef
     custom_view.columns = {'list': [{'id': '0'}]}
-    custom_view.filters = {"filter": "done", "filter-status": "on"}
+    custom_view.filters = {'filter': 'done', 'filter-status': 'on'}
     custom_view.visibility = 'any'
     custom_view.store()
 
diff --git a/tests/api/test_formdata.py b/tests/api/test_formdata.py
index 1b1ec0506..c0e242e20 100644
--- a/tests/api/test_formdata.py
+++ b/tests/api/test_formdata.py
@@ -564,7 +564,7 @@ def test_formdata_edit(pub, local_user):
     # bad payload: not a dict, missing data entry
     get_app(pub).post_json(
         sign_uri('/api/forms/test/%s/' % formdata.id, user=local_user),
-        "not a dict",
+        'not a dict',
         status=400,
     )
     get_app(pub).post_json(
@@ -2711,14 +2711,14 @@ def test_api_geojson_formdata(pub, local_user):
         if field['label'] == 'User Label':
             assert field['varname'] == 'user_label'
             assert field['value'] == username
-            assert field['html_value'] == "&lt;font color=&quot;red&quot;&gt;Jean Darmette&lt;/font&gt;"
+            assert field['html_value'] == '&lt;font color=&quot;red&quot;&gt;Jean Darmette&lt;/font&gt;'
         if field['label'] == 'foobar':
             assert field['varname'] == 'foobar'
             assert field['value'] == foobar
-            assert field['html_value'] == "&lt;font color=&quot;red&quot;&gt;FOO BAR&lt;/font&gt;"
+            assert field['html_value'] == '&lt;font color=&quot;red&quot;&gt;FOO BAR&lt;/font&gt;'
         if field['label'] == 'foobar1':
             assert field['varname'] is None
-            assert field['value'] == "test.txt"
+            assert field['value'] == 'test.txt'
             assert field['html_value'] == (
                 '<div class="file-field"><a download="test.txt" href="http://example.net/backoffice/management/test/28/download?f=1">'
                 '<span>test.txt</span></a></div>'
diff --git a/tests/api/test_formdef.py b/tests/api/test_formdef.py
index 2de6c69a3..803988542 100644
--- a/tests/api/test_formdef.py
+++ b/tests/api/test_formdef.py
@@ -925,10 +925,10 @@ def test_formdef_submit_structured(pub, local_user):
 
     with responses.RequestsMock() as rsps:
         json_data = {
-            "data": [
-                {"id": 0, "text": "zéro", "foo": "bar"},
-                {"id": 1, "text": "uné", "foo": "bar1"},
-                {"id": 2, "text": "deux", "foo": "bar2"},
+            'data': [
+                {'id': 0, 'text': 'zéro', 'foo': 'bar'},
+                {'id': 1, 'text': 'uné', 'foo': 'bar1'},
+                {'id': 2, 'text': 'deux', 'foo': 'bar2'},
             ]
         }
         rsps.get('http://datasource.com', json=json_data)
@@ -1020,9 +1020,9 @@ def test_formdef_submit_structured_with_block_field(pub, local_user):
 
     with responses.RequestsMock() as rsps:
         json_data = {
-            "data": [
-                {"id": 0, "text": "zéro", "foo": "bar"},
-                {"id": 2, "text": "deux", "foo": "bar2"},
+            'data': [
+                {'id': 0, 'text': 'zéro', 'foo': 'bar'},
+                {'id': 2, 'text': 'deux', 'foo': 'bar2'},
             ]
         }
         rsps.get('http://datasource.com', json=json_data)
diff --git a/tests/backoffice_pages/test_all.py b/tests/backoffice_pages/test_all.py
index 4e1f60ee5..847fa8944 100644
--- a/tests/backoffice_pages/test_all.py
+++ b/tests/backoffice_pages/test_all.py
@@ -996,11 +996,11 @@ def test_backoffice_multi_actions_oldest_form(pub):
     workflow.id = '2'
     action = workflow.add_global_action('Mark as duplicates')
     jump = action.add_action('jump')
-    jump.condition = {'type': 'django', 'value': "mass_action_index != 0"}
+    jump.condition = {'type': 'django', 'value': 'mass_action_index != 0'}
     jump.status = 'rejected'
 
     jump2 = action.add_action('jump')
-    jump2.condition = {'type': 'django', 'value': "mass_action_index == 0"}
+    jump2.condition = {'type': 'django', 'value': 'mass_action_index == 0'}
     jump2.status = 'accepted'
 
     register_comment = workflow.possible_status[2].add_action('register-comment', id='_comment')
@@ -3496,7 +3496,7 @@ def test_count_open(pub):
     # check the callback parameter is ignored, that we still get the default
     # criterias when it's set.
     resp = login(get_app(pub)).get('/backoffice/management/count?callback=toto')
-    assert "20" in resp.text
+    assert '20' in resp.text
 
 
 def test_count_backoffice_drafts(pub):
diff --git a/tests/backoffice_pages/test_carddata.py b/tests/backoffice_pages/test_carddata.py
index 2dd94374c..738d3f0d8 100644
--- a/tests/backoffice_pages/test_carddata.py
+++ b/tests/backoffice_pages/test_carddata.py
@@ -429,7 +429,7 @@ def test_backoffice_cards_import_data_from_csv(pub):
         '"value",'
         '"id1|id2|...",'
         '"value"'
-        "\r\n" % (pub.get_default_position(), today)
+        '\r\n' % (pub.get_default_position(), today)
     )
 
     # missing file
diff --git a/tests/backoffice_pages/test_filters.py b/tests/backoffice_pages/test_filters.py
index 8b6195642..1b41b7d73 100644
--- a/tests/backoffice_pages/test_filters.py
+++ b/tests/backoffice_pages/test_filters.py
@@ -411,10 +411,10 @@ def test_backoffice_item_filter(pub):
     resp.forms['listing-settings']['filter-4-operator'].value = 'between'
     for value in [
         card_ids['baz'],
-        "%s|%s|%s" % (card_ids['baz'], card_ids['bar'], card_ids['foo']),
-        "|",
-        "%s|" % card_ids['baz'],
-        "|%s" % card_ids['baz'],
+        '%s|%s|%s' % (card_ids['baz'], card_ids['bar'], card_ids['foo']),
+        '|',
+        '%s|' % card_ids['baz'],
+        '|%s' % card_ids['baz'],
     ]:
         resp.forms['listing-settings']['filter-4-value'].force_value(value)
         resp = resp.forms['listing-settings'].submit()
diff --git a/tests/backoffice_pages/test_form_inspect.py b/tests/backoffice_pages/test_form_inspect.py
index 7c13b0840..d15646990 100644
--- a/tests/backoffice_pages/test_form_inspect.py
+++ b/tests/backoffice_pages/test_form_inspect.py
@@ -248,7 +248,7 @@ def test_inspect_page(pub, local_user):
 
     # test tools
     resp = app.get('%sinspect' % formdata.get_url(backoffice=True), status=200)
-    assert "Test tool" in resp.text
+    assert 'Test tool' in resp.text
 
     resp.form['test_mode'] = 'python-condition'
 
diff --git a/tests/backoffice_pages/test_submission.py b/tests/backoffice_pages/test_submission.py
index 96f9942ca..f5f5eb216 100644
--- a/tests/backoffice_pages/test_submission.py
+++ b/tests/backoffice_pages/test_submission.py
@@ -655,7 +655,7 @@ def test_backoffice_submission_drafts(pub):
     assert resp.form['f1'].value == 'test submission'
 
     resp = resp.form.submit('submit')
-    assert "Check values then click submit." in resp.text
+    assert 'Check values then click submit.' in resp.text
     resp = resp.form.submit('submit')
     # check it kept the same id
     assert resp.location == 'http://example.net/backoffice/management/form-title/%s/' % formdata_no
diff --git a/tests/form_pages/test_all.py b/tests/form_pages/test_all.py
index d4a5fbf3b..4d1540e14 100644
--- a/tests/form_pages/test_all.py
+++ b/tests/form_pages/test_all.py
@@ -1089,7 +1089,7 @@ def test_form_multi_page_condition_on_first_page(pub):
     resp = get_app(pub).get('/test/')
     formdef.data_class().wipe()
     # should be on second page already
-    assert resp.pyquery(".buttons button.form-previous[hidden][disabled]")
+    assert resp.pyquery('.buttons button.form-previous[hidden][disabled]')
     resp.form['f3'] = 'foo'
     assert_current_page(resp, '2nd page')
     resp = resp.form.submit('submit')  # -> 3rd page
@@ -1102,7 +1102,7 @@ def test_form_multi_page_condition_on_first_page(pub):
     resp = resp.form.submit('previous')  # -> 2nd page
     assert_current_page(resp, '2nd page')
     assert resp.form['f3']
-    assert resp.pyquery(".buttons button.form-previous[hidden][disabled]")
+    assert resp.pyquery('.buttons button.form-previous[hidden][disabled]')
 
 
 def test_form_multi_page_condition_on_first_and_next(pub):
@@ -9070,10 +9070,10 @@ def test_form_item_timetable_data_source(pub, http_requests):
 
     with responses.RequestsMock() as rsps:
         data = {
-            "data": [
-                {"id": "1", "datetime": "2021-01-12 10:00:00", "text": "event 1"},
-                {"id": "2", "datetime": "2021-01-13 10:20:00", "text": "event 2"},
-                {"id": "3", "datetime": "2021-01-14 10:40:00", "text": "event 3"},
+            'data': [
+                {'id': '1', 'datetime': '2021-01-12 10:00:00', 'text': 'event 1'},
+                {'id': '2', 'datetime': '2021-01-13 10:20:00', 'text': 'event 2'},
+                {'id': '3', 'datetime': '2021-01-14 10:40:00', 'text': 'event 3'},
             ]
         }
         rsps.get('http://remote.example.net/api/datetimes', json=data)
@@ -9124,10 +9124,10 @@ def test_form_item_timetable_data_source_with_date_alignment(pub, http_requests)
 
     with responses.RequestsMock() as rsps:
         data = {
-            "data": [
-                {"id": "1", "datetime": "2021-01-12 10:00:00", "text": "event 1"},
-                {"id": "2", "datetime": "2021-01-13 10:20:00", "text": "event 2"},
-                {"id": "3", "datetime": "2021-01-14 10:40:00", "text": "event 3"},
+            'data': [
+                {'id': '1', 'datetime': '2021-01-12 10:00:00', 'text': 'event 1'},
+                {'id': '2', 'datetime': '2021-01-13 10:20:00', 'text': 'event 2'},
+                {'id': '3', 'datetime': '2021-01-14 10:40:00', 'text': 'event 3'},
             ]
         }
         rsps.get('http://remote.example.net/api/datetimes', json=data)
diff --git a/tests/form_pages/test_formdata.py b/tests/form_pages/test_formdata.py
index 47f79c910..ef82bc88f 100644
--- a/tests/form_pages/test_formdata.py
+++ b/tests/form_pages/test_formdata.py
@@ -837,7 +837,7 @@ def test_formdata_generated_document_odt_to_pdf_download_push_to_portfolio(
     resp = login(get_app(pub), username='foo', password='foo').get(form_location)
     with responses.RequestsMock() as rsps:
         rsps.post(
-            'http://fargo.example.net/api/documents/push/', status=400, json={"code": "document-exists"}
+            'http://fargo.example.net/api/documents/push/', status=400, json={'code': 'document-exists'}
         )
         resp = resp.form.submit('button_export_to')
         assert len(rsps.calls) == 1
diff --git a/tests/form_pages/test_live.py b/tests/form_pages/test_live.py
index 5078b6906..5d772caec 100644
--- a/tests/form_pages/test_live.py
+++ b/tests/form_pages/test_live.py
@@ -796,15 +796,15 @@ def test_field_live_timetable_select(pub, http_requests):
 
     with responses.RequestsMock() as rsps:
         data = {
-            "data": [
-                {"id": "1", "datetime": "2021-01-12 10:00:00", "text": "event 1", "api": {}},
-                {"id": "2", "datetime": "2021-01-13 10:20:00", "text": "event 2", "api": {}},
+            'data': [
+                {'id': '1', 'datetime': '2021-01-12 10:00:00', 'text': 'event 1', 'api': {}},
+                {'id': '2', 'datetime': '2021-01-13 10:20:00', 'text': 'event 2', 'api': {}},
                 {
-                    "id": "3",
-                    "datetime": "2021-01-14 10:40:00",
-                    "text": "event 3",
-                    "api": {},
-                    "disabled": True,
+                    'id': '3',
+                    'datetime': '2021-01-14 10:40:00',
+                    'text': 'event 3',
+                    'api': {},
+                    'disabled': True,
                 },
             ]
         }
@@ -2170,7 +2170,7 @@ def test_comment_from_card_field(pub):
     for i, value in enumerate(['foo', 'bar']):
         carddata = carddef.data_class()()
         carddata.data = {
-            '0': "%s {{ form_var_foo }}" % value,
+            '0': '%s {{ form_var_foo }}' % value,
         }
         carddata.just_created()
         carddata.store()
diff --git a/tests/test_datasource.py b/tests/test_datasource.py
index b47fab384..80f26cb46 100644
--- a/tests/test_datasource.py
+++ b/tests/test_datasource.py
@@ -265,7 +265,7 @@ def test_item_field_jsonvalue_datasource(requests_pub):
 
 
 def test_jsonvalue_datasource(pub):
-    plain_list = [{"id": "1", "text": "foo"}, {"id": "2", "text": "bar"}]
+    plain_list = [{'id': '1', 'text': 'foo'}, {'id': '2', 'text': 'bar'}]
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list)}
     assert data_sources.get_items(datasource) == [
         ('1', 'foo', '1', {'id': '1', 'text': 'foo'}),
@@ -277,7 +277,7 @@ def test_jsonvalue_datasource(pub):
     ]
 
     # with key
-    plain_list = [{"id": "1", "text": "foo", "key": "a"}, {"id": "2", "text": "bar", "key": "b"}]
+    plain_list = [{'id': '1', 'text': 'foo', 'key': 'a'}, {'id': '2', 'text': 'bar', 'key': 'b'}]
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list)}
     assert data_sources.get_items(datasource) == [
         ('1', 'foo', 'a', {'id': '1', 'key': 'a', 'text': 'foo'}),
@@ -308,7 +308,7 @@ def test_jsonvalue_datasource_errors(pub):
 
     # not a list of dict
     pub.loggederror_class.wipe()
-    plain_list = ["foobar"]
+    plain_list = ['foobar']
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list), 'record_on_errors': True}
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
@@ -317,7 +317,7 @@ def test_jsonvalue_datasource_errors(pub):
     assert logged_error.summary == "[DATASOURCE] JSON data source ('[\"foobar\"]') gave a non usable result"
 
     pub.loggederror_class.wipe()
-    plain_list = [{'foo': 'bar'}, "foobar"]
+    plain_list = [{'foo': 'bar'}, 'foobar']
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list), 'record_on_errors': True}
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
@@ -330,7 +330,7 @@ def test_jsonvalue_datasource_errors(pub):
 
     # no id found
     pub.loggederror_class.wipe()
-    plain_list = [{"text": "foo"}, {"id": "2", "text": "bar"}]
+    plain_list = [{'text': 'foo'}, {'id': '2', 'text': 'bar'}]
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list), 'record_on_errors': True}
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
@@ -342,7 +342,7 @@ def test_jsonvalue_datasource_errors(pub):
     )
 
     pub.loggederror_class.wipe()
-    plain_list = [{"id": "1", "text": "foo"}, {"id": "", "text": "bar"}]
+    plain_list = [{'id': '1', 'text': 'foo'}, {'id': '', 'text': 'bar'}]
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list), 'record_on_errors': True}
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
@@ -355,7 +355,7 @@ def test_jsonvalue_datasource_errors(pub):
 
     # no text found
     pub.loggederror_class.wipe()
-    plain_list = [{"id": "1"}, {"id": "2", "text": "bar"}]
+    plain_list = [{'id': '1'}, {'id': '2', 'text': 'bar'}]
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list), 'record_on_errors': True}
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
@@ -367,7 +367,7 @@ def test_jsonvalue_datasource_errors(pub):
     )
 
     pub.loggederror_class.wipe()
-    plain_list = [{"id": "1", "text": "foo"}, {"id": "2", "text": ""}]
+    plain_list = [{'id': '1', 'text': 'foo'}, {'id': '2', 'text': ''}]
     datasource = {'type': 'jsonvalue', 'value': json.dumps(plain_list), 'record_on_errors': True}
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
@@ -384,7 +384,7 @@ def test_jsonvalue_datasource_errors(pub):
     assert data_sources.get_items(datasource) == []
     assert pub.loggederror_class.count() == 1
     logged_error = pub.loggederror_class.select()[0]
-    assert logged_error.summary == "[DATASOURCE] JSON data source (None) gave a non usable result"
+    assert logged_error.summary == '[DATASOURCE] JSON data source (None) gave a non usable result'
 
 
 def test_json_datasource(pub, requests_pub):
@@ -688,8 +688,8 @@ def test_json_datasource_bad_url(pub, error_email, http_requests, emails):
     logged_error = pub.loggederror_class.select()[0]
     assert logged_error.workflow_id is None
     assert (
-        logged_error.summary == "[DATASOURCE] Error loading JSON data source "
-        "(error in HTTP request to http://remote.example.net/404 (status: 404))"
+        logged_error.summary == '[DATASOURCE] Error loading JSON data source '
+        '(error in HTTP request to http://remote.example.net/404 (status: 404))'
     )
 
     datasource = {
@@ -706,7 +706,7 @@ def test_json_datasource_bad_url(pub, error_email, http_requests, emails):
     assert logged_error.workflow_id is None
     assert (
         logged_error.summary
-        == "[DATASOURCE] Error reading JSON data source output (Expecting value: line 1 column 1 (char 0))"
+        == '[DATASOURCE] Error reading JSON data source output (Expecting value: line 1 column 1 (char 0))'
     )
 
     datasource = {
@@ -720,7 +720,7 @@ def test_json_datasource_bad_url(pub, error_email, http_requests, emails):
     assert pub.loggederror_class.count() == 3
     logged_error = pub.loggederror_class.select(order_by='id')[2]
     assert logged_error.workflow_id is None
-    assert logged_error.summary.startswith("[DATASOURCE] Error loading JSON data source (error")
+    assert logged_error.summary.startswith('[DATASOURCE] Error loading JSON data source (error')
 
     datasource = {
         'type': 'json',
@@ -733,7 +733,7 @@ def test_json_datasource_bad_url(pub, error_email, http_requests, emails):
     assert pub.loggederror_class.count() == 4
     logged_error = pub.loggederror_class.select(order_by='id')[3]
     assert logged_error.workflow_id is None
-    assert logged_error.summary == "[DATASOURCE] Error reading JSON data source output (err 1)"
+    assert logged_error.summary == '[DATASOURCE] Error reading JSON data source output (err 1)'
 
 
 def test_json_datasource_bad_url_scheme(pub, error_email, emails):
@@ -751,7 +751,7 @@ def test_json_datasource_bad_url_scheme(pub, error_email, emails):
     assert logged_error.workflow_id is None
     assert (
         logged_error.summary
-        == "[DATASOURCE] Error loading JSON data source (invalid scheme in URL foo://bar)"
+        == '[DATASOURCE] Error loading JSON data source (invalid scheme in URL foo://bar)'
     )
 
     datasource = {'type': 'json', 'value': '/bla/blo', 'notify_on_errors': True, 'record_on_errors': True}
@@ -762,7 +762,7 @@ def test_json_datasource_bad_url_scheme(pub, error_email, emails):
     logged_error = pub.loggederror_class.select(order_by='id')[1]
     assert logged_error.workflow_id is None
     assert (
-        logged_error.summary == "[DATASOURCE] Error loading JSON data source (invalid scheme in URL /bla/blo)"
+        logged_error.summary == '[DATASOURCE] Error loading JSON data source (invalid scheme in URL /bla/blo)'
     )
 
 
@@ -771,7 +771,7 @@ def test_json_datasource_bad_url_scheme(pub, error_email, emails):
 def test_json_datasource_bad_qs_data(pub, error_email, emails, notify, record):
     datasource = {
         'type': 'json',
-        'value': "https://whatever.com/json",
+        'value': 'https://whatever.com/json',
         'qs_data': {'foo': '{% for invalid %}', 'bar': '{{ valid }}'},
         'notify_on_errors': notify,
         'record_on_errors': record,
@@ -1121,8 +1121,8 @@ def test_geojson_datasource_bad_url(pub, http_requests, error_email, emails):
     logged_error = pub.loggederror_class.select()[0]
     assert logged_error.workflow_id is None
     assert (
-        logged_error.summary == "[DATASOURCE] Error loading JSON data source "
-        "(error in HTTP request to http://remote.example.net/404 (status: 404))"
+        logged_error.summary == '[DATASOURCE] Error loading JSON data source '
+        '(error in HTTP request to http://remote.example.net/404 (status: 404))'
     )
 
     datasource = {
@@ -1139,7 +1139,7 @@ def test_geojson_datasource_bad_url(pub, http_requests, error_email, emails):
     assert logged_error.workflow_id is None
     assert (
         logged_error.summary
-        == "[DATASOURCE] Error reading JSON data source output (Expecting value: line 1 column 1 (char 0))"
+        == '[DATASOURCE] Error reading JSON data source output (Expecting value: line 1 column 1 (char 0))'
     )
 
     datasource = {
@@ -1154,7 +1154,7 @@ def test_geojson_datasource_bad_url(pub, http_requests, error_email, emails):
     assert pub.loggederror_class.count() == 3
     logged_error = pub.loggederror_class.select(order_by='id')[2]
     assert logged_error.workflow_id is None
-    assert logged_error.summary.startswith("[DATASOURCE] Error loading JSON data source (error")
+    assert logged_error.summary.startswith('[DATASOURCE] Error loading JSON data source (error')
 
     datasource = {
         'type': 'geojson',
@@ -1167,7 +1167,7 @@ def test_geojson_datasource_bad_url(pub, http_requests, error_email, emails):
     assert pub.loggederror_class.count() == 4
     logged_error = pub.loggederror_class.select(order_by='id')[3]
     assert logged_error.workflow_id is None
-    assert logged_error.summary == "[DATASOURCE] Error reading JSON data source output (err 1)"
+    assert logged_error.summary == '[DATASOURCE] Error reading JSON data source output (err 1)'
 
     datasource = {
         'type': 'geojson',
@@ -1180,7 +1180,7 @@ def test_geojson_datasource_bad_url(pub, http_requests, error_email, emails):
     assert pub.loggederror_class.count() == 5
     logged_error = pub.loggederror_class.select(order_by='id')[4]
     assert logged_error.workflow_id is None
-    assert logged_error.summary == "[DATASOURCE] Error reading JSON data source output (err_desc :()"
+    assert logged_error.summary == '[DATASOURCE] Error reading JSON data source output (err_desc :()'
 
     datasource = {
         'type': 'geojson',
@@ -1198,7 +1198,7 @@ def test_geojson_datasource_bad_url(pub, http_requests, error_email, emails):
     assert logged_error.workflow_id is None
     assert (
         logged_error.summary
-        == "[DATASOURCE] Error reading JSON data source output (err_desc :(, err_class foo_bar, err bug)"
+        == '[DATASOURCE] Error reading JSON data source output (err_desc :(, err_class foo_bar, err bug)'
     )
 
 
@@ -1216,7 +1216,7 @@ def test_geojson_datasource_bad_url_scheme(pub, error_email, emails):
     assert logged_error.workflow_id is None
     assert (
         logged_error.summary
-        == "[DATASOURCE] Error loading JSON data source (invalid scheme in URL foo://bar)"
+        == '[DATASOURCE] Error loading JSON data source (invalid scheme in URL foo://bar)'
     )
 
     datasource = {'type': 'geojson', 'value': '/bla/blo', 'notify_on_errors': True, 'record_on_errors': True}
@@ -1227,7 +1227,7 @@ def test_geojson_datasource_bad_url_scheme(pub, error_email, emails):
     logged_error = pub.loggederror_class.select(order_by='id')[1]
     assert logged_error.workflow_id is None
     assert (
-        logged_error.summary == "[DATASOURCE] Error loading JSON data source (invalid scheme in URL /bla/blo)"
+        logged_error.summary == '[DATASOURCE] Error loading JSON data source (invalid scheme in URL /bla/blo)'
     )
 
 
@@ -1335,7 +1335,7 @@ def test_data_source_unicode(pub):
 
     NamedDataSource.wipe()
     data_source = NamedDataSource(name='foobar')
-    data_source.data_source = {'type': 'json', 'value': "https://whatever.com/json"}
+    data_source.data_source = {'type': 'json', 'value': 'https://whatever.com/json'}
     data_source.store()
 
     data_source2 = NamedDataSource.select()[0]
@@ -1343,12 +1343,12 @@ def test_data_source_unicode(pub):
     with responses.RequestsMock() as rsps:
         rsps.get(
             'https://whatever.com/json',
-            json={"data": [{"id": 0, "text": "zéro"}, {"id": 1, "text": "uné"}, {"id": 2, "text": "deux"}]},
+            json={'data': [{'id': 0, 'text': 'zéro'}, {'id': 1, 'text': 'uné'}, {'id': 2, 'text': 'deux'}]},
         )
         assert data_sources.get_items({'type': 'foobar'}) == [
-            ('0', 'zéro', '0', {"id": 0, "text": "zéro"}),
-            ('1', 'uné', '1', {"id": 1, "text": "uné"}),
-            ('2', 'deux', '2', {"id": 2, "text": "deux"}),
+            ('0', 'zéro', '0', {'id': 0, 'text': 'zéro'}),
+            ('1', 'uné', '1', {'id': 1, 'text': 'uné'}),
+            ('2', 'deux', '2', {'id': 2, 'text': 'deux'}),
         ]
 
 
@@ -1356,12 +1356,12 @@ def test_data_source_unicode(pub):
 def test_data_source_signed(no_request_pub, qs_data):
     NamedDataSource.wipe()
     data_source = NamedDataSource(name='foobar')
-    data_source.data_source = {'type': 'json', 'value': "https://api.example.com/json"}
+    data_source.data_source = {'type': 'json', 'value': 'https://api.example.com/json'}
     data_source.qs_data = qs_data
     data_source.store()
 
     with responses.RequestsMock() as rsps:
-        rsps.get('https://api.example.com/json', json={"data": [{"id": 0, "text": "zero"}]})
+        rsps.get('https://api.example.com/json', json={'data': [{'id': 0, 'text': 'zero'}]})
         assert len(data_sources.get_items({'type': 'foobar'})) == 1
         signed_url = rsps.calls[-1].request.url
     assert signed_url.startswith('https://api.example.com/json?')
@@ -1377,10 +1377,10 @@ def test_data_source_signed(no_request_pub, qs_data):
         assert querystring['arg1'][0] == 'val1'
         assert querystring['arg2'][0] == 'val2'
 
-    data_source.data_source = {'type': 'json', 'value': "https://api.example.com/json?foo=bar"}
+    data_source.data_source = {'type': 'json', 'value': 'https://api.example.com/json?foo=bar'}
     data_source.store()
     with responses.RequestsMock() as rsps:
-        rsps.get('https://api.example.com/json', json={"data": [{"id": 0, "text": "zero"}]})
+        rsps.get('https://api.example.com/json', json={'data': [{'id': 0, 'text': 'zero'}]})
         assert len(data_sources.get_items({'type': 'foobar'})) == 1
         signed_url = rsps.calls[-1].request.url
     assert signed_url.startswith('https://api.example.com/json?')
@@ -1396,10 +1396,10 @@ def test_data_source_signed(no_request_pub, qs_data):
         assert querystring['arg1'][0] == 'val1'
         assert querystring['arg2'][0] == 'val2'
 
-    data_source.data_source = {'type': 'json', 'value': "https://no-secret.example.com/json"}
+    data_source.data_source = {'type': 'json', 'value': 'https://no-secret.example.com/json'}
     data_source.store()
     with responses.RequestsMock() as rsps:
-        rsps.get('https://no-secret.example.com/json', json={"data": [{"id": 0, "text": "zero"}]})
+        rsps.get('https://no-secret.example.com/json', json={'data': [{'id': 0, 'text': 'zero'}]})
         assert len(data_sources.get_items({'type': 'foobar'})) == 1
         unsigned_url = rsps.calls[-1].request.url
     if qs_data:
@@ -1407,10 +1407,10 @@ def test_data_source_signed(no_request_pub, qs_data):
     else:
         assert unsigned_url == 'https://no-secret.example.com/json'
 
-    data_source.data_source = {'type': 'json', 'value': "https://no-secret.example.com/json?foo=bar"}
+    data_source.data_source = {'type': 'json', 'value': 'https://no-secret.example.com/json?foo=bar'}
     data_source.store()
     with responses.RequestsMock() as rsps:
-        rsps.get('https://no-secret.example.com/json', json={"data": [{"id": 0, "text": "zero"}]})
+        rsps.get('https://no-secret.example.com/json', json={'data': [{'id': 0, 'text': 'zero'}]})
         assert len(data_sources.get_items({'type': 'foobar'})) == 1
         unsigned_url = rsps.calls[-1].request.url
     if qs_data:
@@ -1583,7 +1583,7 @@ def test_data_source_in_template(pub):
     pub.substitutions.feed(formdata)
 
     data_source = NamedDataSource(name='foobar')
-    data_source.data_source = {'type': 'json', 'value': "https://example.invalid/json?t={{form_var_foo}}"}
+    data_source.data_source = {'type': 'json', 'value': 'https://example.invalid/json?t={{form_var_foo}}'}
     data_source.store()
 
     with pub.complex_data():
@@ -1591,10 +1591,10 @@ def test_data_source_in_template(pub):
             rsps.get(
                 'https://example.invalid/json',
                 json={
-                    "data": [{"id": 0, "text": "zéro"}, {"id": 1, "text": "uné"}, {"id": 2, "text": "deux"}],
-                    "meta": {
-                        "foo": "bar",
-                        "blah": {"a": "b", "c": "d"},
+                    'data': [{'id': 0, 'text': 'zéro'}, {'id': 1, 'text': 'uné'}, {'id': 2, 'text': 'deux'}],
+                    'meta': {
+                        'foo': 'bar',
+                        'blah': {'a': 'b', 'c': 'd'},
                     },
                 },
             )
diff --git a/tests/test_datasource_chrono.py b/tests/test_datasource_chrono.py
index 30cc5982f..906b1142f 100644
--- a/tests/test_datasource_chrono.py
+++ b/tests/test_datasource_chrono.py
@@ -30,38 +30,38 @@ def pub(request):
 
 AGENDA_EVENTS_DATA = [
     {
-        "api": {
-            "datetimes_url": "http://chrono.example.net/api/agenda/events-A/datetimes/",
+        'api': {
+            'datetimes_url': 'http://chrono.example.net/api/agenda/events-A/datetimes/',
         },
-        "id": "events-A",
-        "kind": "events",
-        "text": "Events A",
+        'id': 'events-A',
+        'kind': 'events',
+        'text': 'Events A',
     },
     {
-        "api": {
-            "datetimes_url": "http://chrono.example.net/api/agenda/events-B/datetimes/",
+        'api': {
+            'datetimes_url': 'http://chrono.example.net/api/agenda/events-B/datetimes/',
         },
-        "id": "events-B",
-        "kind": "events",
-        "text": "Events B",
+        'id': 'events-B',
+        'kind': 'events',
+        'text': 'Events B',
     },
 ]
 
 
 AGENDA_MEETINGS_DATA = [
     {
-        "api": {"meetings_url": "http://chrono.example.net/api/agenda/meetings-A/meetings/"},
-        "id": "meetings-A",
-        "kind": "meetings",
-        "text": "Meetings A",
+        'api': {'meetings_url': 'http://chrono.example.net/api/agenda/meetings-A/meetings/'},
+        'id': 'meetings-A',
+        'kind': 'meetings',
+        'text': 'Meetings A',
     },
     {
-        "api": {
-            "meetings_url": "http://chrono.example.net/api/agenda/virtual-B/meetings/",
+        'api': {
+            'meetings_url': 'http://chrono.example.net/api/agenda/virtual-B/meetings/',
         },
-        "id": "virtual-B",
-        "kind": "virtual",
-        "text": "Virtual B",
+        'id': 'virtual-B',
+        'kind': 'virtual',
+        'text': 'Virtual B',
     },
 ]
 
@@ -69,30 +69,30 @@ AGENDA_MEETINGS_DATA = [
 AGENDA_MEETING_TYPES_DATA = {
     'meetings-A': [
         {
-            "api": {
-                "datetimes_url": "http://chrono.example.net/api/agenda/meetings-A/meetings/mt-1/datetimes/"
+            'api': {
+                'datetimes_url': 'http://chrono.example.net/api/agenda/meetings-A/meetings/mt-1/datetimes/'
             },
-            "id": "mt-1",
-            "text": "MT 1",
-            "duration": 30,
+            'id': 'mt-1',
+            'text': 'MT 1',
+            'duration': 30,
         },
         {
-            "api": {
-                "datetimes_url": "http://chrono.example.net/api/agenda/meetings-A/meetings/mt-2/datetimes/"
+            'api': {
+                'datetimes_url': 'http://chrono.example.net/api/agenda/meetings-A/meetings/mt-2/datetimes/'
             },
-            "id": "mt-2",
-            "text": "MT 2",
-            "duration": 60,
+            'id': 'mt-2',
+            'text': 'MT 2',
+            'duration': 60,
         },
     ],
     'virtual-B': [
         {
-            "api": {
-                "datetimes_url": "http://chrono.example.net/api/agenda/virtual-B/meetings/mt-3/datetimes/"
+            'api': {
+                'datetimes_url': 'http://chrono.example.net/api/agenda/virtual-B/meetings/mt-3/datetimes/'
             },
-            "id": "mt-3",
-            "text": "MT 3",
-            "duration": 60,
+            'id': 'mt-3',
+            'text': 'MT 3',
+            'duration': 60,
         },
     ],
 }
@@ -124,7 +124,7 @@ def test_collect_agenda_data(pub, chrono_url):
     pub.load_site_options()
     NamedDataSource.wipe()
 
-    responses.get('http://chrono.example.net/api/agenda/', json={"data": []})
+    responses.get('http://chrono.example.net/api/agenda/', json={'data': []})
     assert collect_agenda_data(pub) == []
     assert len(responses.calls) == 1
     assert responses.calls[-1].request.url == 'http://chrono.example.net/api/agenda/'
@@ -137,7 +137,7 @@ def test_collect_agenda_data(pub, chrono_url):
 
     # events agenda
     responses.reset()
-    responses.get('http://chrono.example.net/api/agenda/', json={"data": AGENDA_EVENTS_DATA})
+    responses.get('http://chrono.example.net/api/agenda/', json={'data': AGENDA_EVENTS_DATA})
 
     assert collect_agenda_data(pub) == [
         {
@@ -156,14 +156,14 @@ def test_collect_agenda_data(pub, chrono_url):
 
     # meetings agenda
     responses.reset()
-    responses.get('http://chrono.example.net/api/agenda/', json={"data": AGENDA_MEETINGS_DATA})
+    responses.get('http://chrono.example.net/api/agenda/', json={'data': AGENDA_MEETINGS_DATA})
     responses.get(
         'http://chrono.example.net/api/agenda/meetings-A/meetings/',
-        json={"data": AGENDA_MEETING_TYPES_DATA['meetings-A']},
+        json={'data': AGENDA_MEETING_TYPES_DATA['meetings-A']},
     )
     responses.get(
         'http://chrono.example.net/api/agenda/virtual-B/meetings/',
-        json={"data": AGENDA_MEETING_TYPES_DATA['virtual-B']},
+        json={'data': AGENDA_MEETING_TYPES_DATA['virtual-B']},
     )
 
     assert collect_agenda_data(pub) == [
@@ -209,10 +209,10 @@ def test_collect_agenda_data(pub, chrono_url):
     assert responses.calls[2].request.url == 'http://chrono.example.net/api/agenda/virtual-B/meetings/'
     # if meeting types could not be collected
     responses.reset()
-    responses.get('http://chrono.example.net/api/agenda/', json={"data": AGENDA_MEETINGS_DATA})
+    responses.get('http://chrono.example.net/api/agenda/', json={'data': AGENDA_MEETINGS_DATA})
     responses.get(
         'http://chrono.example.net/api/agenda/meetings-A/meetings/',
-        json={"data": AGENDA_MEETING_TYPES_DATA['meetings-A']},
+        json={'data': AGENDA_MEETING_TYPES_DATA['meetings-A']},
     )
     responses.get('http://chrono.example.net/api/agenda/virtual-B/meetings/', body=ConnectionError('...'))
 
@@ -223,7 +223,7 @@ def test_collect_agenda_data(pub, chrono_url):
     assert responses.calls[2].request.url == 'http://chrono.example.net/api/agenda/virtual-B/meetings/'
 
     responses.reset()
-    responses.get('http://chrono.example.net/api/agenda/', json={"data": AGENDA_MEETINGS_DATA})
+    responses.get('http://chrono.example.net/api/agenda/', json={'data': AGENDA_MEETINGS_DATA})
     responses.get('http://chrono.example.net/api/agenda/meetings-A/meetings/', body=ConnectionError('...'))
 
     assert collect_agenda_data(pub) is None
diff --git a/tests/test_formdata.py b/tests/test_formdata.py
index 4d90a6c80..4860d45ad 100644
--- a/tests/test_formdata.py
+++ b/tests/test_formdata.py
@@ -494,9 +494,9 @@ def test_get_json_export_dict_evolution(pub, local_user):
     evo.who = '_submitter'
     d.evolution = [evo]
     d.store()
-    evo.add_part(JournalEvolutionPart(d, "ok", None))
-    evo.add_part(JournalWsCallErrorPart("summary", "label", "data"))
-    evo.add_part(JournalAssignationErrorPart("summary", "label"))
+    evo.add_part(JournalEvolutionPart(d, 'ok', None))
+    evo.add_part(JournalWsCallErrorPart('summary', 'label', 'data'))
+    evo.add_part(JournalAssignationErrorPart('summary', 'label'))
     evo = Evolution()
     evo.time = time.localtime()
     evo.status = 'wf-%s' % st_finished.id
diff --git a/tests/test_hobo_notify.py b/tests/test_hobo_notify.py
index c9b01474e..5694f30db 100644
--- a/tests/test_hobo_notify.py
+++ b/tests/test_hobo_notify.py
@@ -127,7 +127,7 @@ def test_process_notification_role(pub):
     assert old_role.name == 'Service état civil'
     assert old_role.uuid == uuid2
     assert old_role.slug == 'service-ett-civil'
-    assert old_role.details == "Rôle du service état civil"
+    assert old_role.details == 'Rôle du service état civil'
     assert old_role.emails == ['etat-civil@example.com']
     assert old_role.emails_to_members is True
     assert old_role.allows_backoffice_access is False
@@ -136,7 +136,7 @@ def test_process_notification_role(pub):
     assert new_role.name == 'Service enfance'
     assert new_role.slug == 'service-enfance'
     assert new_role.uuid == uuid1
-    assert new_role.details == "Rôle du service petite enfance"
+    assert new_role.details == 'Rôle du service petite enfance'
     assert new_role.emails == ['petite-enfance@example.com']
     assert new_role.emails_to_members is False
     assert new_role.allows_backoffice_access is False
diff --git a/tests/test_hobo_sql.py b/tests/test_hobo_sql.py
index ec6f8533b..6fed5edc3 100644
--- a/tests/test_hobo_sql.py
+++ b/tests/test_hobo_sql.py
@@ -18,10 +18,10 @@ from wcs.sql import cleanup_connection
 from .utilities import clean_temporary_pub, create_temporary_pub
 
 CONFIG = {
-    "postgresql": {
-        "createdb-connection-params": {"database": "postgres", "user": os.environ['USER']},
-        "database-template-name": "%s",
-        "user": os.environ['USER'],
+    'postgresql': {
+        'createdb-connection-params': {'database': 'postgres', 'user': os.environ['USER']},
+        'database-template-name': '%s',
+        'user': os.environ['USER'],
     }
 }
 
diff --git a/tests/test_snapshots.py b/tests/test_snapshots.py
index 096ba28b0..f6cf40549 100644
--- a/tests/test_snapshots.py
+++ b/tests/test_snapshots.py
@@ -94,7 +94,7 @@ def test_snapshot_basics(pub):
     assert snapshot2.instance  # possible to restore
 
     # no diff with latest snap but label is given
-    pub.snapshot_class.snap(instance=formdef, label="foo bar")
+    pub.snapshot_class.snap(instance=formdef, label='foo bar')
     assert pub.snapshot_class.count() == 3
     snapshot3 = pub.snapshot_class.get_latest('formdef', formdef.id)
     assert snapshot3.serialization is None
@@ -114,7 +114,7 @@ def test_snapshot_basics(pub):
     assert snapshot4.instance  # possible to restore
 
     # no diff with latest snap but label is given
-    pub.snapshot_class.snap(instance=formdef, label="foo bar")
+    pub.snapshot_class.snap(instance=formdef, label='foo bar')
     assert pub.snapshot_class.count() == 5
     snapshot5 = pub.snapshot_class.get_latest('formdef', formdef.id)
     assert snapshot5.serialization is None
diff --git a/tests/test_strftime.py b/tests/test_strftime.py
index da5d9121c..58bbbf977 100644
--- a/tests/test_strftime.py
+++ b/tests/test_strftime.py
@@ -6,13 +6,13 @@ from wcs.qommon.misc import strftime
 def test():
     # Make sure that the day names are in order
     # from 1/1/1800 until 1/1/2100
-    s = strftime("%Y has the same days as 1980 and 2008", datetime.date(1800, 9, 23))
-    if s != "1800 has the same days as 1980 and 2008":
+    s = strftime('%Y has the same days as 1980 and 2008', datetime.date(1800, 9, 23))
+    if s != '1800 has the same days as 1980 and 2008':
         raise AssertionError(s)
 
     days = []
     for i in range(1, 10):
-        days.append(datetime.date(2000, 1, i).strftime("%A"))
+        days.append(datetime.date(2000, 1, i).strftime('%A'))
     nextday = {}
     for i in range(8):
         nextday[days[i]] = days[i + 1]
diff --git a/tests/test_templates.py b/tests/test_templates.py
index c0ca7c256..cb7b878de 100644
--- a/tests/test_templates.py
+++ b/tests/test_templates.py
@@ -222,7 +222,7 @@ def test_unaccent_templatetag(pub):
     assert tmpl.render({'foo': 42}) == ''
     assert pub.loggederror_class.count() == 1
     logged_error = pub.loggederror_class.select(order_by='id')[0]
-    assert logged_error.summary == "Failed to apply unaccent filter on value (42)"
+    assert logged_error.summary == 'Failed to apply unaccent filter on value (42)'
     assert tmpl.render({'foo': ['a', 'z']}) == ''
     assert pub.loggederror_class.count() == 2
     logged_error = pub.loggederror_class.select(order_by='id')[1]
@@ -485,8 +485,8 @@ def test_mathematics_templatetag():
     # using strings
     assert tmpl.render({'term1': '1.1', 'term2': 0}) == '1.1'
     assert tmpl.render({'term1': 'not a number', 'term2': 1.2}) == ''
-    assert tmpl.render({'term1': 0.3, 'term2': "1"}) == '1.3'
-    assert tmpl.render({'term1': 1.4, 'term2': "not a number"}) == ''
+    assert tmpl.render({'term1': 0.3, 'term2': '1'}) == '1.3'
+    assert tmpl.render({'term1': 1.4, 'term2': 'not a number'}) == ''
 
     # add
     assert tmpl.render({'term1': 4, 'term2': -0.9}) == '3.1'
@@ -717,7 +717,7 @@ def test_get_filter():
     assert tmpl.render({'foo': ['bar', 'baz']}) == 'bar'
 
     tmpl = Template('{{ foo|get:0|default_if_none:"" }}')
-    assert tmpl.render({'foo': ""}) == ''
+    assert tmpl.render({'foo': ''}) == ''
     assert tmpl.render({'foo': None}) == ''
     assert tmpl.render({'foo': 23}) == ''
 
diff --git a/tests/test_upload_storage.py b/tests/test_upload_storage.py
index 7b0825490..9c2724b3a 100644
--- a/tests/test_upload_storage.py
+++ b/tests/test_upload_storage.py
@@ -109,7 +109,7 @@ def test_form_file_field_upload_storage(wscall, pub):
     wscall.return_value = (
         None,
         200,
-        json.dumps({"err": 0, "data": {"redirect_url": "https://crypto.example.net/"}}),
+        json.dumps({'err': 0, 'data': {'redirect_url': 'https://crypto.example.net/'}}),
     )
 
     with open(os.path.join(os.path.dirname(__file__), 'image-with-gps-data.jpeg'), 'rb') as fd:
@@ -143,11 +143,11 @@ def test_form_file_field_upload_storage(wscall, pub):
         200,
         json.dumps(
             {
-                "err": 0,
-                "data": {
-                    "redirect_url": "https://crypto.example.net/",
-                    "backoffice_redirect_url": None,
-                    "frontoffice_redirect_url": None,
+                'err': 0,
+                'data': {
+                    'redirect_url': 'https://crypto.example.net/',
+                    'backoffice_redirect_url': None,
+                    'frontoffice_redirect_url': None,
                 },
             }
         ),
@@ -180,7 +180,7 @@ def test_form_file_field_upload_storage(wscall, pub):
     wscall.return_value = (
         None,
         200,
-        json.dumps({"err": 0, "data": {"redirect_url": "https://crypto.example.net/"}}),
+        json.dumps({'err': 0, 'data': {'redirect_url': 'https://crypto.example.net/'}}),
     )
     resp = get_app(pub).get('/test/')
     resp.forms[0]['f0$file'] = upload_0
@@ -206,7 +206,7 @@ def test_form_file_field_upload_storage(wscall, pub):
     wscall.return_value = (
         None,
         200,
-        json.dumps({"err": 0, "data": {"redirect_url": "https://crypto.example.net/"}}),
+        json.dumps({'err': 0, 'data': {'redirect_url': 'https://crypto.example.net/'}}),
     )
     resp = get_app(pub).get('/test/')
     resp.forms[0]['f0$file'] = upload_0
@@ -295,7 +295,7 @@ def test_remoteopaque_in_attachmentevolutionpart(wscall, pub):
     wscall.return_value = (
         None,
         200,
-        json.dumps({"err": 0, "data": {"redirect_url": "https://crypto.example.net/"}}),
+        json.dumps({'err': 0, 'data': {'redirect_url': 'https://crypto.example.net/'}}),
     )
 
     with open(os.path.join(os.path.dirname(__file__), 'image-with-gps-data.jpeg'), 'rb') as fd:
diff --git a/tests/utilities.py b/tests/utilities.py
index a63dd1b98..644a6d4e8 100644
--- a/tests/utilities.py
+++ b/tests/utilities.py
@@ -349,22 +349,22 @@ class HttpRequestsMocking:
         self.requests_mock.get('http://remote.example.net/404', status=404, body='page not found')
         self.requests_mock.get('http://remote.example.net/404-json', status=404, json={'err': 'not-found'})
         self.requests_mock.get('http://remote.example.net/500', status=500, body='internal server error')
-        self.requests_mock.get('http://remote.example.net/json', json={"foo": "bar"})
-        self.requests_mock.post('http://remote.example.net/json', json={"foo": "bar"})
-        self.requests_mock.delete('http://remote.example.net/json', json={"foo": "bar"})
+        self.requests_mock.get('http://remote.example.net/json', json={'foo': 'bar'})
+        self.requests_mock.post('http://remote.example.net/json', json={'foo': 'bar'})
+        self.requests_mock.delete('http://remote.example.net/json', json={'foo': 'bar'})
         self.requests_mock.get(
-            'http://remote.example.net/json-list', json={"data": [{"id": "a", "text": "b"}]}
+            'http://remote.example.net/json-list', json={'data': [{'id': 'a', 'text': 'b'}]}
         )
         self.requests_mock.get(
             'http://remote.example.net/json-list-extra',
-            json={"data": [{"id": "a", "text": "b", "foo": "bar"}]},
+            json={'data': [{'id': 'a', 'text': 'b', 'foo': 'bar'}]},
         )
         self.requests_mock.get(
             'http://remote.example.net/json-list-extra-with-disabled',
             json={
-                "data": [
-                    {"id": "a", "text": "b", "foo": "bar"},
-                    {"id": "c", "text": "d", "foo": "baz", "disabled": True},
+                'data': [
+                    {'id': 'a', 'text': 'b', 'foo': 'bar'},
+                    {'id': 'c', 'text': 'd', 'foo': 'baz', 'disabled': True},
                 ]
             },
         )
@@ -377,16 +377,16 @@ class HttpRequestsMocking:
             content_type='text/xml',
             headers={'x-error-code': '1'},
         )
-        self.requests_mock.get('http://remote.example.net/json-err0', json={"data": "foo", "err": 0})
-        self.requests_mock.get('http://remote.example.net/json-err0int', json={"data": "foo", "err": "0"})
-        self.requests_mock.get('http://remote.example.net/json-err1', json={"data": "", "err": 1})
-        self.requests_mock.get('http://remote.example.net/json-err1int', json={"data": "", "err": "1"})
+        self.requests_mock.get('http://remote.example.net/json-err0', json={'data': 'foo', 'err': 0})
+        self.requests_mock.get('http://remote.example.net/json-err0int', json={'data': 'foo', 'err': '0'})
+        self.requests_mock.get('http://remote.example.net/json-err1', json={'data': '', 'err': 1})
+        self.requests_mock.get('http://remote.example.net/json-err1int', json={'data': '', 'err': '1'})
         self.requests_mock.get(
             'http://remote.example.net/json-err1-with-desc', json={'data': '', 'err': 1, 'err_desc': ':('}
         )
-        self.requests_mock.get('http://remote.example.net/json-errstr', json={"data": "", "err": "bug"})
+        self.requests_mock.get('http://remote.example.net/json-errstr', json={'data': '', 'err': 'bug'})
         self.requests_mock.get(
-            'http://remote.example.net/json-list-err1', json={"data": [{"id": "a", "text": "b"}], "err": 1}
+            'http://remote.example.net/json-list-err1', json={'data': [{'id': 'a', 'text': 'b'}], 'err': 1}
         )
         self.requests_mock.get(
             'http://remote.example.net/json-list-err1bis',
@@ -407,14 +407,14 @@ class HttpRequestsMocking:
         )
         self.requests_mock.get('http://remote.example.net/json-errstr', json={'data': '', 'err': 'bug'})
         self.requests_mock.get(
-            'http://remote.example.net/json-errheader0', json={"foo": "bar"}, headers={'x-error-code': '0'}
+            'http://remote.example.net/json-errheader0', json={'foo': 'bar'}, headers={'x-error-code': '0'}
         )
         self.requests_mock.get(
-            'http://remote.example.net/json-errheader1', json={"foo": "bar"}, headers={'x-error-code': '1'}
+            'http://remote.example.net/json-errheader1', json={'foo': 'bar'}, headers={'x-error-code': '1'}
         )
         self.requests_mock.get(
             'http://remote.example.net/json-errheaderstr',
-            json={"foo": "bar"},
+            json={'foo': 'bar'},
             headers={'x-error-code': 'bug'},
         )
         self.requests_mock.get(
diff --git a/tests/workflow/test_all.py b/tests/workflow/test_all.py
index 17e495156..ec4ca24fc 100644
--- a/tests/workflow/test_all.py
+++ b/tests/workflow/test_all.py
@@ -2948,7 +2948,7 @@ def test_sms_with_passerelle(pub):
     with mock.patch('wcs.wscalls.get_secret_and_orig') as mocked_secret_and_orig:
         mocked_secret_and_orig.return_value = ('secret', 'localhost')
         with responses.RequestsMock() as rsps:
-            rsps.post('http://passerelle.example.com/send', status=400, json={"err": 1})
+            rsps.post('http://passerelle.example.com/send', status=400, json={'err': 1})
             item.perform(formdata)
             assert pub.loggederror_class.count() == 1
             assert pub.loggederror_class.select()[0].summary == 'Could not send SMS'
diff --git a/tests/workflow/test_backoffice_field.py b/tests/workflow/test_backoffice_field.py
index f8e494974..01ed7e808 100644
--- a/tests/workflow/test_backoffice_field.py
+++ b/tests/workflow/test_backoffice_field.py
@@ -913,7 +913,7 @@ def test_set_backoffice_field_items(pub):
 
     item = SetBackofficeFieldsWorkflowStatusItem()
     item.parent = st1
-    item.fields = [{'field_id': 'bo1', 'value': "=form_var_items_raw"}]
+    item.fields = [{'field_id': 'bo1', 'value': '=form_var_items_raw'}]
     item.perform(formdata)
 
     assert formdata.data['bo1'] == ['a', 'c']
@@ -932,7 +932,7 @@ def test_set_backoffice_field_items(pub):
     pub.substitutions.reset()
     pub.substitutions.feed(formdata)
 
-    item.fields = [{'field_id': 'bo1', 'value': "{{form_var_items_raw}}"}]
+    item.fields = [{'field_id': 'bo1', 'value': '{{form_var_items_raw}}'}]
     item.perform(formdata)
 
     # using a single int
@@ -959,7 +959,7 @@ def test_set_backoffice_field_items(pub):
 
     item = SetBackofficeFieldsWorkflowStatusItem()
     item.parent = st1
-    item.fields = [{'field_id': 'bo1', 'value': "=2"}]
+    item.fields = [{'field_id': 'bo1', 'value': '=2'}]
     item.perform(formdata)
 
     formdata = formdef.data_class().get(formdata.id)
@@ -973,7 +973,7 @@ def test_set_backoffice_field_items(pub):
     pub.loggederror_class.wipe()
     item = SetBackofficeFieldsWorkflowStatusItem()
     item.parent = st1
-    item.fields = [{'field_id': 'bo1', 'value': "=Ellipsis"}]
+    item.fields = [{'field_id': 'bo1', 'value': '=Ellipsis'}]
     item.perform(formdata)
     assert pub.loggederror_class.count() == 1
     logged_error = pub.loggederror_class.select()[0]
@@ -982,7 +982,7 @@ def test_set_backoffice_field_items(pub):
     # using a string with multiple values
     item = SetBackofficeFieldsWorkflowStatusItem()
     item.parent = st1
-    item.fields = [{'field_id': 'bo1', 'value': "1|3"}]
+    item.fields = [{'field_id': 'bo1', 'value': '1|3'}]
     item.perform(formdata)
 
     formdata = formdef.data_class().get(formdata.id)
@@ -1017,7 +1017,7 @@ def test_set_backoffice_field_date(pub):
 
     item = SetBackofficeFieldsWorkflowStatusItem()
     item.parent = st1
-    item.fields = [{'field_id': 'bo1', 'value': "=utils.today()"}]
+    item.fields = [{'field_id': 'bo1', 'value': '=utils.today()'}]
     item.perform(formdata)
 
     formdata = formdef.data_class().get(formdata.id)
@@ -1035,7 +1035,7 @@ def test_set_backoffice_field_date(pub):
 
     item = SetBackofficeFieldsWorkflowStatusItem()
     item.parent = st1
-    item.fields = [{'field_id': 'bo1', 'value': "23/3/2017"}]
+    item.fields = [{'field_id': 'bo1', 'value': '23/3/2017'}]
     item.perform(formdata)
 
     formdata = formdef.data_class().get(formdata.id)
@@ -1478,7 +1478,7 @@ def test_set_backoffice_field_immediate_use(http_requests, pub):
 
     item.fields = [
         {'field_id': 'bo1', 'value': 'X{{form_var_string}}X'},
-        {'field_id': 'bo2', 'value': "Y{{form_var_backoffice_blah}}Y"},
+        {'field_id': 'bo2', 'value': 'Y{{form_var_backoffice_blah}}Y'},
     ]
     pub.substitutions.reset()
     pub.substitutions.feed(formdata)
diff --git a/tests/workflow/test_email.py b/tests/workflow/test_email.py
index 9f7d654e0..f4c6dd332 100644
--- a/tests/workflow/test_email.py
+++ b/tests/workflow/test_email.py
@@ -440,7 +440,7 @@ def test_email_attachments(pub, emails):
     assert emails.emails['foobar']['msg'].get_payload(2).get_content_type() == 'application/json'
     payload1 = emails.emails['foobar']['msg'].get_payload(1)
     payload2 = emails.emails['foobar']['msg'].get_payload(2)
-    assert payload1.get_payload(decode=True) == b"Hello world"
+    assert payload1.get_payload(decode=True) == b'Hello world'
     assert json.loads(force_str(payload2.get_payload(decode=True))) == {'hello': 'world'}
 
     # check with templates
diff --git a/tests/workflow/test_wscall.py b/tests/workflow/test_wscall.py
index a6b0b0bde..3a0b42fb2 100644
--- a/tests/workflow/test_wscall.py
+++ b/tests/workflow/test_wscall.py
@@ -63,7 +63,7 @@ def test_wscall_record_errors(pub):
 
     # error with bytes that can be stored as string
     with responses.RequestsMock() as rsps:
-        rsps.get('http://test', status=404, body=b"test bytes")
+        rsps.get('http://test', status=404, body=b'test bytes')
         wscall.perform(formdata)
         assert formdata.evolution[-1].parts[-1].get_json_export_dict() == {
             'type': 'wscall-error',
diff --git a/wcs/Defaults.py b/wcs/Defaults.py
index eda2bde93..3756684ec 100644
--- a/wcs/Defaults.py
+++ b/wcs/Defaults.py
@@ -14,7 +14,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, see <http://www.gnu.org/licenses/>.
 
-APP_DIR = "/var/lib/wcs"
-DATA_DIR = "/usr/share/wcs"
+APP_DIR = '/var/lib/wcs'
+DATA_DIR = '/usr/share/wcs'
 ERROR_LOG = None
 REDIRECT_ON_UNKNOWN_VHOST = None
diff --git a/wcs/admin/fields.py b/wcs/admin/fields.py
index 32b2cc91d..86f7fd528 100644
--- a/wcs/admin/fields.py
+++ b/wcs/admin/fields.py
@@ -188,7 +188,7 @@ class FieldDefPage(Directory):
             if to_be_deleted:
                 form.add(CheckboxWidget, 'delete_fields', title=_('Also remove all fields from the page'))
         form.add_submit('delete', _('Delete'))
-        form.add_submit("cancel", _("Cancel"))
+        form.add_submit('cancel', _('Cancel'))
         if form.get_widget('cancel').parse():
             return self.redirect_field_anchor(self.field)
         if not form.is_submitted() or form.has_errors():
@@ -251,7 +251,7 @@ class FieldDefPage(Directory):
         if page_fields:
             form.add(CheckboxWidget, 'duplicate_fields', title=_('Also duplicate all fields of the page'))
         form.add_submit('submit', _('Duplicate'))
-        form.add_submit("cancel", _("Cancel"))
+        form.add_submit('cancel', _('Cancel'))
         if form.get_widget('cancel').parse():
             return self.redirect_field_anchor(self.field)
         if not form.is_submitted() or form.has_errors():
diff --git a/wcs/admin/roles.py b/wcs/admin/roles.py
index ce1696485..4a8355de8 100644
--- a/wcs/admin/roles.py
+++ b/wcs/admin/roles.py
@@ -31,11 +31,11 @@ class RoleUI:
             self.role = get_publisher().role_class()
 
     def get_form(self):
-        form = Form(enctype="multipart/form-data")
-        form.add(StringWidget, "name", title=_('Role Name'), required=True, size=30, value=self.role.name)
+        form = Form(enctype='multipart/form-data')
+        form.add(StringWidget, 'name', title=_('Role Name'), required=True, size=30, value=self.role.name)
         form.add(
             TextWidget,
-            "details",
+            'details',
             title=_('Role Details'),
             required=False,
             cols=40,
@@ -63,8 +63,8 @@ class RoleUI:
             title=_('Users holding the role can access to backoffice'),
             value=self.role.allows_backoffice_access,
         )
-        form.add_submit("submit", _("Submit"))
-        form.add_submit("cancel", _("Cancel"))
+        form.add_submit('submit', _('Submit'))
+        form.add_submit('cancel', _('Cancel'))
         return form
 
     def submit_form(self, form):
@@ -86,7 +86,7 @@ class RoleUI:
 
 
 class RolePage(Directory):
-    _q_exports = ['', "edit", "delete"]
+    _q_exports = ['', 'edit', 'delete']
 
     def __init__(self, component):
         try:
@@ -192,9 +192,9 @@ class RolePage(Directory):
 
     def delete(self):
         form = Form(enctype='multipart/form-data')
-        form.widgets.append(HtmlWidget('<p>%s</p>' % _("You are about to irrevocably delete this role.")))
+        form.widgets.append(HtmlWidget('<p>%s</p>' % _('You are about to irrevocably delete this role.')))
         form.add_submit('delete', _('Delete'))
-        form.add_submit("cancel", _("Cancel"))
+        form.add_submit('cancel', _('Cancel'))
         if form.get_widget('cancel').parse():
             return redirect('.')
         if not form.is_submitted() or form.has_errors():
@@ -210,7 +210,7 @@ class RolePage(Directory):
 
 
 class RolesDirectory(Directory):
-    _q_exports = ["", "new"]
+    _q_exports = ['', 'new']
 
     def _q_traverse(self, path):
         get_response().breadcrumb.append(('roles/', _('Roles')))
diff --git a/wcs/admin/settings.py b/wcs/admin/settings.py
index 603477f55..837a8c940 100644
--- a/wcs/admin/settings.py
+++ b/wcs/admin/settings.py
@@ -749,7 +749,7 @@ class SettingsDirectory(AccessControlled, Directory):
         if get_request().form.get('download'):
             return self.export_download()
 
-        form = Form(enctype="multipart/form-data")
+        form = Form(enctype='multipart/form-data')
         form.add(CheckboxWidget, 'formdefs', title=_('Forms'), value=True)
         form.add(CheckboxWidget, 'carddefs', title=_('Card Models'), value=True)
         form.add(CheckboxWidget, 'workflows', title=_('Workflows'), value=True)
@@ -1265,7 +1265,7 @@ $('#form_default-zoom-level').on('change', function() {
             return redirect('.')
 
     def debug_options(self):
-        form = Form(enctype="multipart/form-data")
+        form = Form(enctype='multipart/form-data')
         debug_cfg = get_cfg('debug', {})
         form.add(
             StringWidget,
diff --git a/wcs/admin/users.py b/wcs/admin/users.py
index 05281d1f2..bedfd5a85 100644
--- a/wcs/admin/users.py
+++ b/wcs/admin/users.py
@@ -220,9 +220,9 @@ class UserPage(Directory):
                     r += str(_('Account federated with %s') % label)
                     r += htmltext('<br />')
                     if federation.localNameIdentifier:
-                        r += str(_("local: ") + federation.localNameIdentifier.content)
+                        r += str(_('local: ') + federation.localNameIdentifier.content)
                     if federation.remoteNameIdentifier:
-                        r += str(_("remote: ") + federation.remoteNameIdentifier.content)
+                        r += str(_('remote: ') + federation.remoteNameIdentifier.content)
                     r += htmltext('</li>')
                 r += htmltext('</ul></div>')
 
@@ -278,9 +278,9 @@ class UserPage(Directory):
 
     def delete(self):
         form = Form(enctype='multipart/form-data')
-        form.widgets.append(HtmlWidget('<p>%s</p>' % _("You are about to irrevocably delete this user.")))
+        form.widgets.append(HtmlWidget('<p>%s</p>' % _('You are about to irrevocably delete this user.')))
         form.add_submit('delete', _('Delete'))
-        form.add_submit("cancel", _("Cancel"))
+        form.add_submit('cancel', _('Cancel'))
         if form.get_widget('cancel').parse():
             return redirect('.')
         if not form.is_submitted() or form.has_errors():
diff --git a/wcs/admin/workflows.py b/wcs/admin/workflows.py
index eac57a91e..d385179e8 100644
--- a/wcs/admin/workflows.py
+++ b/wcs/admin/workflows.py
@@ -791,7 +791,7 @@ class WorkflowStatusPage(Directory):
         return redirect('.')
 
     def delete(self):
-        form = Form(enctype="multipart/form-data")
+        form = Form(enctype='multipart/form-data')
         if self.workflow.possible_status and len(self.workflow.possible_status) == 1:
             form.widgets.append(
                 HtmlWidget(
@@ -1773,22 +1773,22 @@ class WorkflowPage(Directory):
         return r.getvalue()
 
     def delete(self):
-        form = Form(enctype="multipart/form-data")
+        form = Form(enctype='multipart/form-data')
         from itertools import chain
 
         for objdef in chain(FormDef.select(), CardDef.select()):
             if objdef.workflow_id == self.workflow.id:
                 form.widgets.append(
-                    HtmlWidget('<p>%s</p>' % _("This workflow is currently in use, you cannot remove it."))
+                    HtmlWidget('<p>%s</p>' % _('This workflow is currently in use, you cannot remove it.'))
                 )
-                form.add_submit("cancel", _("Cancel"))
+                form.add_submit('cancel', _('Cancel'))
                 break
         else:
             form.widgets.append(
-                HtmlWidget('<p>%s</p>' % _("You are about to irrevocably delete this workflow."))
+                HtmlWidget('<p>%s</p>' % _('You are about to irrevocably delete this workflow.'))
             )
             form.add_submit('delete', _('Delete'))
-            form.add_submit("cancel", _("Cancel"))
+            form.add_submit('cancel', _('Cancel'))
         if form.get_widget('cancel').parse():
             return redirect('.')
         if not form.is_submitted() or form.has_errors():
diff --git a/wcs/carddata.py b/wcs/carddata.py
index a683eac22..b3d18877e 100644
--- a/wcs/carddata.py
+++ b/wcs/carddata.py
@@ -125,4 +125,4 @@ class CardData(FormData):
             'file_digest': file_digest,
         }
         token = get_session().create_token('card-file-by-token', context)
-        return "/api/card-file-by-token/%s" % token.id
+        return '/api/card-file-by-token/%s' % token.id
diff --git a/wcs/ctl/delete_tenant.py b/wcs/ctl/delete_tenant.py
index e3065118c..f14fbcade 100644
--- a/wcs/ctl/delete_tenant.py
+++ b/wcs/ctl/delete_tenant.py
@@ -99,7 +99,7 @@ class CmdDeleteTenant(Command):
 
                 else:
                     schema_name = 'removed_%s_%s' % (deletion_date, dbname)
-                    cur.execute("CREATE SCHEMA %s" % schema_name[:63])
+                    cur.execute('CREATE SCHEMA %s' % schema_name[:63])
                     for table_name in tables_names:
                         cur.execute('ALTER TABLE %s SET SCHEMA %s' % (table_name, schema_name[:63]))
 
diff --git a/wcs/data_sources.py b/wcs/data_sources.py
index 60dd3ed1b..74591c7e3 100644
--- a/wcs/data_sources.py
+++ b/wcs/data_sources.py
@@ -301,7 +301,7 @@ def get_json_from_url(
         entries = misc.json_loads(misc.urlopen(url).read())
         if not isinstance(entries, dict):
             raise ValueError('not a json dict')
-        if entries.get('err') not in (None, 0, "0"):
+        if entries.get('err') not in (None, 0, '0'):
             details = []
             for key in ['err_desc', 'err_class']:
                 if entries.get(key):
diff --git a/wcs/formats/en/formats.py b/wcs/formats/en/formats.py
index 1362306ce..d53473d55 100644
--- a/wcs/formats/en/formats.py
+++ b/wcs/formats/en/formats.py
@@ -1,2 +1,2 @@
 DATETIME_FORMAT = 'Y-m-d H:i'
-DATE_FORMAT = "Y-m-d"
+DATE_FORMAT = 'Y-m-d'
diff --git a/wcs/formats/fr/formats.py b/wcs/formats/fr/formats.py
index 99222ed10..107ac81d9 100644
--- a/wcs/formats/fr/formats.py
+++ b/wcs/formats/fr/formats.py
@@ -1,2 +1,2 @@
 DATETIME_FORMAT = 'd/m/Y H:i'
-DATE_FORMAT = "d/m/Y"
+DATE_FORMAT = 'd/m/Y'
diff --git a/wcs/formdef.py b/wcs/formdef.py
index bbe830a78..6acfb9333 100644
--- a/wcs/formdef.py
+++ b/wcs/formdef.py
@@ -350,16 +350,16 @@ class FormDef(StorableObject):
             if order_by not in [field.contextual_varname, 'f%s' % field.contextual_id]:
                 continue
             if field.contextual_varname == order_by:
-                order_by = "f%s" % field.contextual_id
+                order_by = 'f%s' % field.contextual_id
             if getattr(field, 'block_field', None) and 'f%s' % field.contextual_id == order_by:
                 # field of block field, sort on the first element
                 order_by = "f%s->'data'->0->>'%s%s'" % (
                     field.block_field.id,
                     field.id,
-                    "_display" if field.store_display_value else "",
+                    '_display' if field.store_display_value else '',
                 )
             elif field.store_display_value:
-                order_by += "_display"
+                order_by += '_display'
             break
         return '%s%s' % (direction, order_by)
 
diff --git a/wcs/forms/common.py b/wcs/forms/common.py
index 109ef0e0b..0de2940da 100644
--- a/wcs/forms/common.py
+++ b/wcs/forms/common.py
@@ -450,7 +450,7 @@ class FormStatusPage(Directory, FormTemplateMixin):
             response.set_status(303)
             response.headers['location'] = url
             response.content_type = 'text/plain'
-            return "Your browser should redirect you"
+            return 'Your browser should redirect you'
 
     def export_to_json(
         self,
diff --git a/wcs/publisher.py b/wcs/publisher.py
index e9b66618b..e1014b465 100644
--- a/wcs/publisher.py
+++ b/wcs/publisher.py
@@ -137,14 +137,14 @@ class WcsPublisher(QommonPublisher):
 
     @classmethod
     def configure(cls, config):
-        if config.has_option("main", "app_dir"):
-            cls.APP_DIR = config.get("main", "app_dir")
-        if config.has_option("main", "data_dir"):
-            cls.DATA_DIR = config.get("main", "data_dir")
-        if config.has_option("main", "error_log"):
-            cls.ERROR_LOG = config.get("main", "error_log")
-        if config.has_option("main", "missing_appdir_redirect"):
-            cls.missing_appdir_redirect = config.get("main", "missing_appdir_redirect")
+        if config.has_option('main', 'app_dir'):
+            cls.APP_DIR = config.get('main', 'app_dir')
+        if config.has_option('main', 'data_dir'):
+            cls.DATA_DIR = config.get('main', 'data_dir')
+        if config.has_option('main', 'error_log'):
+            cls.ERROR_LOG = config.get('main', 'error_log')
+        if config.has_option('main', 'missing_appdir_redirect'):
+            cls.missing_appdir_redirect = config.get('main', 'missing_appdir_redirect')
 
     @classmethod
     def register_cronjobs(cls):
diff --git a/wcs/qommon/admin/menu.py b/wcs/qommon/admin/menu.py
index 9d5062c94..e8b079c22 100644
--- a/wcs/qommon/admin/menu.py
+++ b/wcs/qommon/admin/menu.py
@@ -49,7 +49,7 @@ def _find_vc_version():
                 ) as process:
                     version = process.communicate()[0].splitlines()[-1].split()[2]
                     if process.returncode == 0:
-                        return "%s %s (Debian)" % (package, version.decode())
+                        return '%s %s (Debian)' % (package, version.decode())
             except Exception:
                 pass
         return None
@@ -74,7 +74,7 @@ def _find_vc_version():
                 output = process.communicate()[0]
             starred_line = [x for x in output.splitlines() if x.startswith(b'*')][0]
             branch = str(starred_line.split()[1].decode('ascii'))
-            url = "https://repos.entrouvert.org/%s.git/commit/?id=%s" % (package, rev)
+            url = 'https://repos.entrouvert.org/%s.git/commit/?id=%s' % (package, rev)
             if version:
                 revision = htmltext('%s %s <a href="%s">git %s\'s branch rev:%s</a>') % (
                     package,
@@ -94,9 +94,9 @@ def _find_vc_version():
             pass
     else:
         if version:
-            revision = "%s %s (Tarball)" % (package, version)
+            revision = '%s %s (Tarball)' % (package, version)
         else:
-            revision = "%s (Tarball)" % (package)
+            revision = '%s (Tarball)' % (package)
 
     if not revision:
         return None
diff --git a/wcs/qommon/apps.py b/wcs/qommon/apps.py
index 3ca4ebd9b..8944bb3d3 100644
--- a/wcs/qommon/apps.py
+++ b/wcs/qommon/apps.py
@@ -68,7 +68,7 @@ class _Timer(TenantAwareThread):
 
 class _MainThread(TenantAwareThread):
     def __init__(self):
-        super().__init__(name="MainThread")
+        super().__init__(name='MainThread')
         self._Thread__started.set()
         self._set_ident()
         with threading._active_limbo_lock:
@@ -82,18 +82,18 @@ class _MainThread(TenantAwareThread):
         t = threading._pickSomeNonDaemonThread()
         if t:
             if __debug__:
-                self._note("%s: waiting for other threads", self)
+                self._note('%s: waiting for other threads', self)
         while t:
             t.join()
             t = threading._pickSomeNonDaemonThread()
         if __debug__:
-            self._note("%s: exiting", self)
+            self._note('%s: exiting', self)
         self._Thread__delete()
 
 
 class _DummyThread(TenantAwareThread):
     def __init__(self):
-        super().__init__(name=threading._newname("Dummy-%d"), daemon=True)
+        super().__init__(name=threading._newname('Dummy-%d'), daemon=True)
 
         self._started.set()
         self._set_ident()
@@ -108,7 +108,7 @@ class _DummyThread(TenantAwareThread):
         return True
 
     def join(self, timeout=None):
-        assert False, "cannot join a dummy thread"
+        assert False, 'cannot join a dummy thread'
 
 
 class AppConfig(django.apps.AppConfig):
diff --git a/wcs/qommon/ctl.py b/wcs/qommon/ctl.py
index 292a638b4..f3a879b84 100644
--- a/wcs/qommon/ctl.py
+++ b/wcs/qommon/ctl.py
@@ -59,9 +59,9 @@ class Command:
             self.config.add_section('main')
         sub_options, args = self.parse_args(args)
         if sub_options.app_dir:
-            self.config.set("main", "app_dir", sub_options.app_dir)
+            self.config.set('main', 'app_dir', sub_options.app_dir)
         if sub_options.data_dir:
-            self.config.set("main", "data_dir", sub_options.data_dir)
+            self.config.set('main', 'data_dir', sub_options.data_dir)
         return self.execute(base_options, sub_options, args)
 
     def parse_args(self, args):
@@ -97,7 +97,7 @@ class Ctl:
             help=_('use a non default configuration file'),
         )
         self.parser.add_option(
-            '--help', action='callback', callback=self.print_help, help=_("Display this help and exit")
+            '--help', action='callback', callback=self.print_help, help=_('Display this help and exit')
         )
 
     def load_all_commands(self, ignore_errors=True):
diff --git a/wcs/qommon/errors.py b/wcs/qommon/errors.py
index da2bee030..d0a9d1476 100644
--- a/wcs/qommon/errors.py
+++ b/wcs/qommon/errors.py
@@ -142,8 +142,8 @@ class InspectException(Exception):
 
 TraversalError.title = _('Page not found')
 TraversalError.description = _(
-    "The requested link does not exist on this site.  If "
-    "you arrived here by following a link from an external "
+    'The requested link does not exist on this site.  If '
+    'you arrived here by following a link from an external '
     "page, please inform that page's maintainer."
 )
 
diff --git a/wcs/qommon/ezt.py b/wcs/qommon/ezt.py
index 10cc720da..8e9be2467 100644
--- a/wcs/qommon/ezt.py
+++ b/wcs/qommon/ezt.py
@@ -288,7 +288,7 @@ class Template:
             self.parse_file(fname, base_format)
 
     def parse_file(self, fname, base_format=FORMAT_RAW):
-        "fname -> a string object with pathname of file containg an EZT template."
+        'fname -> a string object with pathname of file containg an EZT template.'
 
         self.parse(_FileReader(fname), base_format)
 
@@ -509,7 +509,7 @@ class Template:
         self._execute(self._parse(reader.read_other(fname)), fp, ctx)
 
     def _cmd_if_any(self, args, fp, ctx):
-        "If any value is a non-empty string or non-empty list, then T else F."
+        'If any value is a non-empty string or non-empty list, then T else F.'
         (valrefs, t_section, f_section) = args
         value = 0
         for valref in valrefs:
@@ -580,7 +580,7 @@ class Template:
 
 
 def boolean(value):
-    "Return a value suitable for [if-any bool_var] usage in a template."
+    'Return a value suitable for [if-any bool_var] usage in a template.'
     if value:
         return 'yes'
     return None
@@ -755,7 +755,7 @@ class _context:
 
 
 class Reader:
-    "Abstract class which allows EZT to detect Reader objects."
+    'Abstract class which allows EZT to detect Reader objects.'
 
 
 class _FileReader(Reader):
diff --git a/wcs/qommon/form.py b/wcs/qommon/form.py
index 8b01baaeb..7b2411445 100644
--- a/wcs/qommon/form.py
+++ b/wcs/qommon/form.py
@@ -242,7 +242,7 @@ def file_render_content(self):
         attrs['aria-required'] = 'true'
     if self.attrs:
         attrs.update(self.attrs)
-    return htmltag("input", xml_end=True, type=self.HTML_TYPE, name=self.name, value=self.value, **attrs)
+    return htmltag('input', xml_end=True, type=self.HTML_TYPE, name=self.name, value=self.value, **attrs)
 
 
 FileWidget.render_content = file_render_content
@@ -339,12 +339,12 @@ Widget.transfer_form_value = transfer_form_value
 
 class Form(QuixoteForm):
     TOKEN_NOTICE = _(
-        "The form you have submitted is invalid.  Most "
-        "likely it has been successfully submitted once "
-        "already.  Please review the form data "
-        "and submit the form again."
+        'The form you have submitted is invalid.  Most '
+        'likely it has been successfully submitted once '
+        'already.  Please review the form data '
+        'and submit the form again.'
     )
-    ERROR_NOTICE = _("There were errors processing your form.  See below for details.")
+    ERROR_NOTICE = _('There were errors processing your form.  See below for details.')
 
     info = None
     captcha = None
@@ -673,7 +673,7 @@ class StringWidget(QuixoteStringWidget):
             attrs.update(self.attrs)
         if getattr(self, 'inputmode', None):
             attrs['inputmode'] = self.inputmode
-        return htmltag("input", xml_end=True, type=self.HTML_TYPE, name=self.name, value=self.value, **attrs)
+        return htmltag('input', xml_end=True, type=self.HTML_TYPE, name=self.name, value=self.value, **attrs)
 
 
 class DurationWidget(StringWidget):
@@ -744,9 +744,9 @@ class TextWidget(QuixoteTextWidget):
         if attrs.get('readonly') and not self.value:
             attrs['rows'] = 1
         return (
-            htmltag("textarea", name=self.name, **attrs)
-            + htmlescape(self.value or "")
-            + htmltext("</textarea>")
+            htmltag('textarea', name=self.name, **attrs)
+            + htmlescape(self.value or '')
+            + htmltext('</textarea>')
         )
 
 
@@ -780,12 +780,12 @@ class CheckboxWidget(QuixoteCheckboxWidget):
             # hack to restore value on click
             attrs['onclick'] = 'this.checked = !this.checked;'
         checkbox = htmltag(
-            "input",
+            'input',
             xml_end=True,
-            type="checkbox",
+            type='checkbox',
             name=self.name,
-            value="yes",
-            checked=self.value and "checked" or None,
+            value='yes',
+            checked=self.value and 'checked' or None,
             **attrs,
         )
         if standalone:
@@ -1179,13 +1179,13 @@ class SingleSelectWidget(quixote.form.widget.SingleSelectWidget):
             attrs['aria-required'] = 'true'
         if self.attrs:
             attrs.update(self.attrs)
-        tags = [htmltag("select", name=self.name, **attrs)]
+        tags = [htmltag('select', name=self.name, **attrs)]
         opened_optgroup = False
         for obj, description, key, attrs in self.full_options:
             if isinstance(obj, OptGroup):
                 if opened_optgroup:
-                    tags.append(htmltext("</optgroup>"))
-                tags.append(htmltag("optgroup", label=obj.title))
+                    tags.append(htmltext('</optgroup>'))
+                tags.append(htmltag('optgroup', label=obj.title))
                 opened_optgroup = True
                 continue
             if self.is_selected(obj):
@@ -1193,13 +1193,13 @@ class SingleSelectWidget(quixote.form.widget.SingleSelectWidget):
             else:
                 selected = None
             if description is None:
-                description = ""
-            r = htmltag("option", value=key, selected=selected, **attrs)
+                description = ''
+            r = htmltag('option', value=key, selected=selected, **attrs)
             tags.append(r + htmlescape(description) + htmltext('</option>'))
         if opened_optgroup:
-            tags.append(htmltext("</optgroup>"))
-        tags.append(htmltext("</select>"))
-        return htmltext("\n").join(tags)
+            tags.append(htmltext('</optgroup>'))
+        tags.append(htmltext('</select>'))
+        return htmltext('\n').join(tags)
 
 
 class ValidationCondition(Condition):
@@ -1973,7 +1973,7 @@ class WidgetList(quixote.form.widget.WidgetList):
         value=None,
         element_type=StringWidget,
         element_kwargs=None,
-        add_element_label="Add row",
+        add_element_label='Add row',
         default_items_count=None,
         max_items=None,
         **kwargs,
@@ -2562,7 +2562,7 @@ class WysiwygTextWidget(TextWidget):
         return (
             htmltag('textarea', name=self.name, **attrs)
             + htmlescape(self.value or '')
-            + htmltext("</textarea>")
+            + htmltext('</textarea>')
         )
 
 
@@ -2864,7 +2864,7 @@ class TableListRowsWidget(WidgetListAsTable):
         return klass
 
     def add_element(self, value=None):
-        name = "element%d" % len(self.element_names)
+        name = 'element%d' % len(self.element_names)
         self.add(self.table_row_class, name, value=value, **self.widget_kwargs)
         self.element_names.append(name)
 
diff --git a/wcs/qommon/http_request.py b/wcs/qommon/http_request.py
index 6c339128d..2737054fa 100644
--- a/wcs/qommon/http_request.py
+++ b/wcs/qommon/http_request.py
@@ -121,20 +121,20 @@ class HTTPRequest(quixote.http_request.HTTPRequest):
         row = '%-15s %r'
 
         if self.form:
-            result.append("Form:")
+            result.append('Form:')
             for k, v in sorted(self.form.items()):
                 result.append(row % (k, v))
 
-        result.append("")
-        result.append("Cookies:")
+        result.append('')
+        result.append('Cookies:')
         for k, v in sorted(self.cookies.items()):
             result.append(row % (k, v))
 
-        result.append("")
-        result.append("Environment:")
+        result.append('')
+        result.append('Environment:')
         for k, v in sorted(self.environ.items()):
             result.append(row % (k, v))
-        return "\n".join(result)
+        return '\n'.join(result)
 
     def process_inputs(self):
         if self.parsed:
@@ -147,7 +147,7 @@ class HTTPRequest(quixote.http_request.HTTPRequest):
             length = int(length)
         except ValueError:
             raise RequestError('invalid content-length header')
-        ctype = self.environ.get("CONTENT_TYPE")
+        ctype = self.environ.get('CONTENT_TYPE')
         if self.django_request:
             self.stdin = self.django_request
         if ctype:
diff --git a/wcs/qommon/humantime.py b/wcs/qommon/humantime.py
index d1e8fe700..65db0d943 100644
--- a/wcs/qommon/humantime.py
+++ b/wcs/qommon/humantime.py
@@ -29,17 +29,17 @@ def list2human(stringlist):
     '''Transform a string list to human enumeration'''
     beginning = stringlist[:-1]
     if not beginning:
-        return "".join(stringlist)
-    return _("%(first)s and %(second)s") % {'first': _(", ").join(beginning), 'second': stringlist[-1]}
+        return ''.join(stringlist)
+    return _('%(first)s and %(second)s') % {'first': _(', ').join(beginning), 'second': stringlist[-1]}
 
 
 _humandurations = (
-    ((_("day"), _("days")), _day),
-    ((_("hour"), _("hours")), _hour),
-    ((_("month"), _("months")), _month),
-    ((_("year"), _("years")), _year),
-    ((_("minute"), _("minutes")), _minute),
-    ((_("second"), _("seconds")), 1),
+    ((_('day'), _('days')), _day),
+    ((_('hour'), _('hours')), _hour),
+    ((_('month'), _('months')), _month),
+    ((_('year'), _('years')), _year),
+    ((_('minute'), _('minutes')), _minute),
+    ((_('second'), _('seconds')), 1),
 )
 
 
@@ -58,7 +58,7 @@ def humanduration2seconds(humanduration):
     seconds = 0
     for words, quantity in _humandurations:
         for word in words:
-            m = re.search(r"(\d+)\s*\b%s\b" % word, humanduration)
+            m = re.search(r'(\d+)\s*\b%s\b' % word, humanduration)
             if m:
                 seconds = seconds + int(m.group(1)) * quantity
                 break
@@ -68,7 +68,7 @@ def humanduration2seconds(humanduration):
 def seconds2humanduration(seconds, short=False):
     """Convert a time range in seconds to a human string representation"""
     if not isinstance(seconds, int):
-        return ""
+        return ''
 
     days = int(seconds / _day)
     seconds = seconds - _day * days
diff --git a/wcs/qommon/ident/idp.py b/wcs/qommon/ident/idp.py
index ee1e56e87..afc3d5909 100644
--- a/wcs/qommon/ident/idp.py
+++ b/wcs/qommon/ident/idp.py
@@ -70,7 +70,7 @@ def get_text_file_preview(filename):
     """
     content = get_file_content(str(filename))
     if content:
-        return htmltext("<pre>%s</pre>") % content
+        return htmltext('<pre>%s</pre>') % content
     else:
         return None
 
@@ -82,7 +82,7 @@ class MethodDirectory(Directory):
         idps = get_cfg('idp', {})
 
         if not lasso:
-            raise Exception("lasso is missing, idp method cannot be used")
+            raise Exception('lasso is missing, idp method cannot be used')
 
         if len(idps) == 0:
             return template.error_page(_('SSO support is not yet configured'))
diff --git a/wcs/qommon/management/commands/collectstatic.py b/wcs/qommon/management/commands/collectstatic.py
index 795131c7e..4b6ce887b 100644
--- a/wcs/qommon/management/commands/collectstatic.py
+++ b/wcs/qommon/management/commands/collectstatic.py
@@ -23,7 +23,7 @@ from wcs.qommon.publisher import get_publisher_class
 
 
 class Command(BaseCommand):
-    help = "Collect static files in a single location."
+    help = 'Collect static files in a single location.'
 
     def add_arguments(self, parser):
         parser.add_argument(
@@ -32,8 +32,8 @@ class Command(BaseCommand):
             action='store_true',
             dest='clear',
             default=False,
-            help="Clear the existing files using the storage "
-            "before trying to copy or link the original file.",
+            help='Clear the existing files using the storage '
+            'before trying to copy or link the original file.',
         )
         parser.add_argument(
             '-l',
@@ -41,7 +41,7 @@ class Command(BaseCommand):
             action='store_true',
             dest='link',
             default=False,
-            help="Create a symbolic link to each file instead of copying.",
+            help='Create a symbolic link to each file instead of copying.',
         )
 
     def handle(self, **options):
diff --git a/wcs/qommon/misc.py b/wcs/qommon/misc.py
index 2a684d4e1..b25b0aa8c 100644
--- a/wcs/qommon/misc.py
+++ b/wcs/qommon/misc.py
@@ -137,9 +137,9 @@ def get_provider_label(provider):
     if not organization:
         return provider.providerId
 
-    name = re.findall("<OrganizationDisplayName.*>(.*?)</OrganizationDisplayName>", organization)
+    name = re.findall('<OrganizationDisplayName.*>(.*?)</OrganizationDisplayName>', organization)
     if not name:
-        name = re.findall("<OrganizationName.*>(.*?)</OrganizationName>", organization)
+        name = re.findall('<OrganizationName.*>(.*?)</OrganizationName>', organization)
         if not name:
             return provider.providerId
     return htmltext(name[0].decode('utf8').encode(get_publisher().site_charset))
@@ -561,10 +561,10 @@ def get_foreground_colour(background_colour):
 def indent_xml(elem, level=0):
     # in-place prettyprint formatter
     # http://effbot.org/zone/element-lib.htm#prettyprint
-    i = "\n" + level * "  "
+    i = '\n' + level * '  '
     if len(elem):
         if not elem.text or not elem.text.strip():
-            elem.text = i + "  "
+            elem.text = i + '  '
         for elem in elem:
             indent_xml(elem, level + 1)
         if not elem.tail or not elem.tail.strip():
diff --git a/wcs/qommon/publisher.py b/wcs/qommon/publisher.py
index 377cee19a..2f4b8b4b9 100644
--- a/wcs/qommon/publisher.py
+++ b/wcs/qommon/publisher.py
@@ -228,7 +228,7 @@ class QommonPublisher(Publisher):
         if limit is None:
             if hasattr(sys, 'tracebacklimit'):
                 limit = sys.tracebacklimit
-        print("Exception:", file=error_file)
+        print('Exception:', file=error_file)
         print("  type = '%s', value = '%s'" % (exc_type, exc_value), file=error_file)
         print('', file=error_file)
 
@@ -255,9 +255,9 @@ class QommonPublisher(Publisher):
                         print(' %5s %s' % (lineno, line.rstrip()), file=error_file)
             print('', file=error_file)
             if locals:
-                print("  locals: ", file=error_file)
+                print('  locals: ', file=error_file)
                 for key, value in locals:
-                    print("     %s =" % key, end=' ', file=error_file)
+                    print('     %s =' % key, end=' ', file=error_file)
                     value = safe_filter.cleanse_setting(key, value)
                     try:
                         repr_value = repr(value)
@@ -265,7 +265,7 @@ class QommonPublisher(Publisher):
                             repr_value = repr_value[:10000] + ' [...]'
                         print(repr_value, file=error_file)
                     except Exception:
-                        print("<ERROR WHILE PRINTING VALUE>", file=error_file)
+                        print('<ERROR WHILE PRINTING VALUE>', file=error_file)
             print('', file=error_file)
             frame = frame.f_back
             n = n + 1
@@ -813,7 +813,7 @@ class QommonPublisher(Publisher):
                 'map-bounds-bottom-right'
             ).split(';')
         attrs['data-map-attribution'] = self.get_site_option('map-attribution') or _(
-            "Map data &copy; "
+            'Map data &copy; '
             "<a href='https://openstreetmap.org'>OpenStreetMap</a> contributors, "
             "<a href='http://creativecommons.org/licenses/by-sa/2.0/'>CC-BY-SA</a>"
         )
diff --git a/wcs/qommon/saml2.py b/wcs/qommon/saml2.py
index 8ade5ecce..8adcd4f33 100644
--- a/wcs/qommon/saml2.py
+++ b/wcs/qommon/saml2.py
@@ -294,7 +294,7 @@ class Saml2Directory(Directory):
     def sso_after_response(self, login):
         try:
             assertion = login.response.assertion[0]
-            last_slash = get_request().get_url().rfind("/")
+            last_slash = get_request().get_url().rfind('/')
             if (
                 assertion.subject.subjectConfirmation.subjectConfirmationData.recipient
                 != get_cfg('sp', {}).get('saml2_base_url') + get_request().get_url()[last_slash:]
@@ -406,7 +406,7 @@ class Saml2Directory(Directory):
         response.set_status(303)
         response.headers['location'] = after_url
         response.content_type = 'text/plain'
-        return "Your browser should redirect you"
+        return 'Your browser should redirect you'
 
     def assertionConsumerPost(self):
         message = get_field('SAMLResponse')
diff --git a/wcs/qommon/storage.py b/wcs/qommon/storage.py
index 62d4ef8a0..dc0bf2a32 100644
--- a/wcs/qommon/storage.py
+++ b/wcs/qommon/storage.py
@@ -86,7 +86,7 @@ def atomic_write(path, content, async_op=False):
         dirname = os.path.dirname(path)
         fd, temp = tempfile.mkstemp(dir=dirname, prefix='.tmp-' + os.path.basename(path) + '-')
         os.fchmod(fd, 0o666 & ~process_umask)
-        f = os.fdopen(fd, "wb")
+        f = os.fdopen(fd, 'wb')
         if hasattr(content, 'read'):
             # file pointer
             def read100k():
diff --git a/wcs/qommon/vendor/locket.py b/wcs/qommon/vendor/locket.py
index 1b4c7ecae..76534611b 100644
--- a/wcs/qommon/vendor/locket.py
+++ b/wcs/qommon/vendor/locket.py
@@ -35,7 +35,7 @@ import threading
 import time
 import weakref
 
-__all__ = ["lock_file"]
+__all__ = ['lock_file']
 
 
 import fcntl
@@ -159,7 +159,7 @@ class _LockFile:
 
     def acquire(self):
         if self._file is None:
-            self._file = open(self._path, "w")  # pylint: disable=consider-using-with
+            self._file = open(self._path, 'w')  # pylint: disable=consider-using-with
         if self._timeout is None:
             _lock_file_blocking(self._file)
         else:
diff --git a/wcs/settings.py b/wcs/settings.py
index 8418c51d2..aaa8f9b0a 100644
--- a/wcs/settings.py
+++ b/wcs/settings.py
@@ -88,13 +88,13 @@ TEMPLATES = [
         'APP_DIRS': False,
         'OPTIONS': {
             'context_processors': [
-                "django.template.context_processors.debug",
-                "django.template.context_processors.i18n",
-                "django.template.context_processors.media",
-                "django.template.context_processors.static",
-                "django.template.context_processors.tz",
-                "django.contrib.messages.context_processors.messages",
-                "wcs.context_processors.publisher",
+                'django.template.context_processors.debug',
+                'django.template.context_processors.i18n',
+                'django.template.context_processors.media',
+                'django.template.context_processors.static',
+                'django.template.context_processors.tz',
+                'django.contrib.messages.context_processors.messages',
+                'wcs.context_processors.publisher',
             ],
             'loaders': [
                 'wcs.utils.TemplateLoader',
diff --git a/wcs/snapshots.py b/wcs/snapshots.py
index d51bdf946..20bd31fd4 100644
--- a/wcs/snapshots.py
+++ b/wcs/snapshots.py
@@ -29,17 +29,17 @@ class UnknownUser:
         return str(_('unknown user'))
 
 
-def indent(tree, space="  ", level=0):
+def indent(tree, space='  ', level=0):
     # backport from Lib/xml/etree/ElementTree.py python 3.9
     if isinstance(tree, ET.ElementTree):
         tree = tree.getroot()
     if level < 0:
-        raise ValueError(f"Initial indentation level must be >= 0, got {level}")
+        raise ValueError(f'Initial indentation level must be >= 0, got {level}')
     if len(tree) == 0:
         return
 
     # Reduce the memory consumption by reusing indentation strings.
-    indentations = ["\n" + level * space]
+    indentations = ['\n' + level * space]
 
     def _indent_children(elem, level):
         # Start a new indentation level for the first child.
@@ -66,8 +66,8 @@ def indent(tree, space="  ", level=0):
     _indent_children(tree, 0)
 
 
-_no_eol = "\\ No newline at end of file"
-_hdr_pat = re.compile(r"^@@ -(\d+),?(\d+)? \+(\d+),?(\d+)? @@$")
+_no_eol = '\\ No newline at end of file'
+_hdr_pat = re.compile(r'^@@ -(\d+),?(\d+)? \+(\d+),?(\d+)? @@$')
 
 
 def make_patch(a, b):
@@ -93,15 +93,15 @@ def apply_patch(s, patch, revert=False):
     t = ''
     i = sl = 0
     (midx, sign) = (1, '+') if not revert else (3, '-')
-    while i < len(p) and p[i].startswith(("---", "+++")):
+    while i < len(p) and p[i].startswith(('---', '+++')):
         i += 1  # skip header lines
     while i < len(p):
         m = _hdr_pat.match(p[i])
         if not m:
-            raise Exception("Bad patch -- regex mismatch [line " + str(i) + "]")
+            raise Exception('Bad patch -- regex mismatch [line ' + str(i) + ']')
         _l = int(m.group(midx)) - 1 + (m.group(midx + 1) == '0')
         if sl > _l or _l > len(s):
-            raise Exception("Bad patch -- bad line num [line " + str(i) + "]")
+            raise Exception('Bad patch -- bad line num [line ' + str(i) + ']')
         t += ''.join(s[sl:_l])
         sl = _l
         i += 1
diff --git a/wcs/sql.py b/wcs/sql.py
index ea7fcfe32..efc28a1c6 100644
--- a/wcs/sql.py
+++ b/wcs/sql.py
@@ -554,20 +554,20 @@ def recreate_trigger(formdef, cur, conn):
     # recreate the trigger function, just so it's uptodate
     table_name = get_formdef_table_name(formdef)
     category_value = formdef.category_id
-    geoloc_base_x_query = "NULL"
-    geoloc_base_y_query = "NULL"
+    geoloc_base_x_query = 'NULL'
+    geoloc_base_y_query = 'NULL'
     if formdef.geolocations and 'base' in formdef.geolocations:
         # default geolocation is in the 'base' key; we have to unstructure the
         # field is the POINT type of postgresql cannot be used directly as it
         # doesn't have an equality operator.
-        geoloc_base_x_query = "NEW.geoloc_base[0]"
-        geoloc_base_y_query = "NEW.geoloc_base[1]"
+        geoloc_base_x_query = 'NEW.geoloc_base[0]'
+        geoloc_base_y_query = 'NEW.geoloc_base[1]'
     if formdef.category_id is None:
-        category_value = "NULL"
+        category_value = 'NULL'
     criticality_levels = len(formdef.workflow.criticality_levels or [0])
     endpoint_status = formdef.workflow.get_endpoint_status()
-    endpoint_status_filter = ", ".join(["'wf-%s'" % x.id for x in endpoint_status])
-    if endpoint_status_filter == "":
+    endpoint_status_filter = ', '.join(["'wf-%s'" % x.id for x in endpoint_status])
+    if endpoint_status_filter == '':
         # not the prettiest in town, but will do fine for now.
         endpoint_status_filter = "'xxxx'"
     formed_name_quotedstring = psycopg2.extensions.QuotedString(formdef.name)
@@ -1481,17 +1481,17 @@ def do_global_views(conn, cur):
     )"""
     )
     cur.execute(
-        '''CREATE INDEX IF NOT EXISTS %s_fts ON %s USING gin(fts)''' % ("wcs_all_forms", "wcs_all_forms")
+        '''CREATE INDEX IF NOT EXISTS %s_fts ON %s USING gin(fts)''' % ('wcs_all_forms', 'wcs_all_forms')
     )
 
     for attr in ('receipt_time', 'anonymised', 'user_id', 'status'):
         cur.execute(
-            '''CREATE INDEX IF NOT EXISTS %s_%s ON %s (%s)''' % ("wcs_all_forms", attr, "wcs_all_forms", attr)
+            '''CREATE INDEX IF NOT EXISTS %s_%s ON %s (%s)''' % ('wcs_all_forms', attr, 'wcs_all_forms', attr)
         )
     for attr in ('concerned_roles_array', 'actions_roles_array'):
         cur.execute(
             '''CREATE INDEX IF NOT EXISTS %s_%s ON %s USING gin (%s)'''
-            % ("wcs_all_forms", attr, "wcs_all_forms", attr)
+            % ('wcs_all_forms', attr, 'wcs_all_forms', attr)
         )
 
     # make sure the table will not be changed while we work on it
@@ -1551,19 +1551,19 @@ def init_global_table(conn=None, cur=None):
     for formdef in FormDef.select():
         category_value = formdef.category_id
         if formdef.category_id is None:
-            category_value = "NULL"
-        geoloc_base_x_query = "NULL"
-        geoloc_base_y_query = "NULL"
+            category_value = 'NULL'
+        geoloc_base_x_query = 'NULL'
+        geoloc_base_y_query = 'NULL'
         if formdef.geolocations and 'base' in formdef.geolocations:
             # default geolocation is in the 'base' key; we have to unstructure the
             # field is the POINT type of postgresql cannot be used directly as it
             # doesn't have an equality operator.
-            geoloc_base_x_query = "geoloc_base[0]"
-            geoloc_base_y_query = "geoloc_base[1]"
+            geoloc_base_x_query = 'geoloc_base[0]'
+            geoloc_base_y_query = 'geoloc_base[1]'
         criticality_levels = len(formdef.workflow.criticality_levels or [0])
         endpoint_status = formdef.workflow.get_endpoint_status()
-        endpoint_status_filter = ", ".join(["'wf-%s'" % x.id for x in endpoint_status])
-        if endpoint_status_filter == "":
+        endpoint_status_filter = ', '.join(["'wf-%s'" % x.id for x in endpoint_status])
+        if endpoint_status_filter == '':
             # not the prettiest in town, but will do fine for now.
             endpoint_status_filter = "'xxxx'"
         formed_name_quotedstring = psycopg2.extensions.QuotedString(formdef.name)
@@ -2082,7 +2082,7 @@ class SqlMixin:
             elif field.key == 'computed':
                 if not isinstance(value, dict):
                     raise ValueError(
-                        "bad data %s (type %s) in computed field %s" % (value, type(value), field.id)
+                        'bad data %s (type %s) in computed field %s' % (value, type(value), field.id)
                     )
                 if value.get('@type') == 'computed-data':
                     value = value.get('data')
@@ -2575,7 +2575,7 @@ class SqlDataMixin(SqlMixin):
             value = row[len(cls._table_static_fields) + i]
             if not value:
                 continue
-            m = re.match(r"\(([^)]+),([^)]+)\)", value)
+            m = re.match(r'\(([^)]+),([^)]+)\)', value)
             o.geolocations[field] = {'lon': float(m.group(1)), 'lat': float(m.group(2))}
 
         o.data = cls._row2obdata(row, cls._formdef)
@@ -3176,7 +3176,7 @@ class TransientData(SqlMixin):
         try:
             cur.execute(sql_statement, sql_dict)
         except psycopg2.IntegrityError as e:
-            if "transient_data_session_id_fkey" not in str(e):
+            if 'transient_data_session_id_fkey' not in str(e):
                 raise
 
         conn.commit()
@@ -5024,7 +5024,7 @@ def get_cron_status():
     conn, cur = get_connection_and_cursor()
     do_meta_table(conn, cur, insert_current_sql_level=False)
     key = 'cron-status-%s' % get_publisher().tenant.hostname
-    cur.execute("SELECT value, updated_at FROM wcs_meta WHERE key = %s", (key,))
+    cur.execute('SELECT value, updated_at FROM wcs_meta WHERE key = %s', (key,))
     row = cur.fetchone()
     conn.commit()
     cur.close()
@@ -5036,7 +5036,7 @@ def get_and_update_cron_status():
     conn, cur = get_connection_and_cursor()
     do_meta_table(conn, cur, insert_current_sql_level=False)
     key = 'cron-status-%s' % get_publisher().tenant.hostname
-    cur.execute("SELECT value, created_at FROM wcs_meta WHERE key = %s FOR UPDATE", (key,))
+    cur.execute('SELECT value, created_at FROM wcs_meta WHERE key = %s FOR UPDATE', (key,))
     row = cur.fetchone()
     timestamp = now()
     if row is None:
@@ -5065,7 +5065,7 @@ def get_and_update_cron_status():
 def mark_cron_status(status):
     conn, cur = get_connection_and_cursor()
     key = 'cron-status-%s' % get_publisher().tenant.hostname
-    cur.execute("UPDATE wcs_meta SET value = %s, updated_at = NOW() WHERE key = %s", (status, key))
+    cur.execute('UPDATE wcs_meta SET value = %s, updated_at = NOW() WHERE key = %s', (status, key))
     conn.commit()
     cur.close()
 
diff --git a/wcs/sql_criterias.py b/wcs/sql_criterias.py
index 1c82fe08b..0c5456b14 100644
--- a/wcs/sql_criterias.py
+++ b/wcs/sql_criterias.py
@@ -122,15 +122,15 @@ class Criteria(wcs.qommon.storage.Criteria):
                 )
             else:
                 # for none values
-                attribute = "COALESCE(%s, ARRAY[]::text[])" % attribute
+                attribute = 'COALESCE(%s, ARRAY[]::text[])' % attribute
             if isinstance(self, Between):
-                return "%s(SELECT 1 FROM UNNEST(%s) bb(aa) WHERE aa >= %%(c%s)s AND aa < %%(c%s)s)" % (
+                return '%s(SELECT 1 FROM UNNEST(%s) bb(aa) WHERE aa >= %%(c%s)s AND aa < %%(c%s)s)' % (
                     getattr(self, 'sql_exists', 'EXISTS'),
                     attribute,
                     id(self.value[0]),
                     id(self.value[1]),
                 )
-            return "%s(SELECT 1 FROM UNNEST(%s) bb(aa) WHERE aa %s %%(c%s)s)" % (
+            return '%s(SELECT 1 FROM UNNEST(%s) bb(aa) WHERE aa %s %%(c%s)s)' % (
                 getattr(self, 'sql_exists', 'EXISTS'),
                 attribute,
                 getattr(self, 'sql_op_exists', self.sql_op),
@@ -218,7 +218,7 @@ class NotEqual(Criteria):
     def as_sql(self):
         if self.field and getattr(self.field, 'block_field', None):
             return super().as_sql()
-        return "(%s is NULL OR %s)" % (self.attribute, super().as_sql())
+        return '(%s is NULL OR %s)' % (self.attribute, super().as_sql())
 
 
 class StrictNotEqual(Criteria):
diff --git a/wcs/statistics/views.py b/wcs/statistics/views.py
index 5fbfe3204..d194f4332 100644
--- a/wcs/statistics/views.py
+++ b/wcs/statistics/views.py
@@ -538,12 +538,12 @@ class FormsCountView(RestrictedView):
         if group_by == 'channel':
             totals_kwargs['group_by'] = 'submission_channel_new'
             totals_kwargs['group_by_clause'] = (
-                "CASE "
+                'CASE '
                 "WHEN submission_channel IN ('web', '') OR submission_channel IS NULL THEN "
                 "CASE WHEN backoffice_submission THEN 'backoffice' ELSE 'web' END "
-                "ELSE submission_channel "
-                "END "
-                "as submission_channel_new, "
+                'ELSE submission_channel '
+                'END '
+                'as submission_channel_new, '
             )
 
             group_labels.update(FormData.get_submission_channels())
diff --git a/wcs/wf/create_formdata.py b/wcs/wf/create_formdata.py
index 2eafacb38..497502ef3 100644
--- a/wcs/wf/create_formdata.py
+++ b/wcs/wf/create_formdata.py
@@ -607,7 +607,7 @@ class CreateFormdataWorkflowStatusItem(WorkflowStatusItem):
                     src.evolution[-1].add_part(
                         JournalAssignationErrorPart(
                             _('Failed to attach user (not found: "%s")') % value,
-                            "%s (%s)" % (self.description, self.formdef.name),
+                            '%s (%s)' % (self.description, self.formdef.name),
                         )
                     )
                     src.store()
diff --git a/wcs/workflows.py b/wcs/workflows.py
index b455c7428..859a7c0d8 100644
--- a/wcs/workflows.py
+++ b/wcs/workflows.py
@@ -70,7 +70,7 @@ from .qommon.template import Template, TemplateError
 from .qommon.upload_storage import PicklableUpload, get_storage_object
 from .roles import get_user_roles, logged_users_role
 
-if not __name__.startswith('wcs.') and __name__ != "__main__":
+if not __name__.startswith('wcs.') and __name__ != '__main__':
     raise ImportError('Import of workflows module must be absolute (import wcs.workflows)')
 
 
diff --git a/wcs/wsgi.py b/wcs/wsgi.py
index 9687aa798..465ec4c14 100644
--- a/wcs/wsgi.py
+++ b/wcs/wsgi.py
@@ -5,5 +5,5 @@ import os
 
 from django.core.wsgi import get_wsgi_application
 
-os.environ.setdefault("DJANGO_SETTINGS_MODULE", "wcs.settings")
+os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'wcs.settings')
 application = get_wsgi_application()
diff --git a/wcsctl.py b/wcsctl.py
index 1c23dbd4f..e5b47510f 100755
--- a/wcsctl.py
+++ b/wcsctl.py
@@ -3,7 +3,7 @@
 import os
 import sys
 
-os.environ.setdefault("DJANGO_SETTINGS_MODULE", "wcs.settings")
+os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'wcs.settings')
 
 import wcs.qommon.ctl