diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index a14705c..ce247d6 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -6,3 +6,13 @@ repos:
     hooks:
     - id: black
       args: ['--target-version', 'py37', '--skip-string-normalization', '--line-length', '110']
+-   repo: https://github.com/PyCQA/isort
+    rev: 5.7.0
+    hooks:
+    - id: isort
+      args: ['--profile', 'black', '--line-length', '110']
+-   repo: https://github.com/asottile/pyupgrade
+    rev: v2.20.0
+    hooks:
+    - id: pyupgrade
+      args: ['--keep-percent-format', '--py37-plus']
diff --git a/README b/README
index fba31ef..16180a8 100644
--- a/README
+++ b/README
@@ -319,7 +319,7 @@ Unit tests are written using pytest and launched using tox, and can be run with:
    tox
 
 Code Style
-----------
+==========
 
 black is used to format the code, using thoses parameters:
 
@@ -328,6 +328,18 @@ black is used to format the code, using thoses parameters:
 There is .pre-commit-config.yaml to use pre-commit to automatically run black
 before commits. (execute `pre-commit install` to install the git hook.)
 
+isort is used to format the imports, using those parameter:
+
+    isort --profile black --line-length 110
+
+pyupgrade is used to automatically upgrade syntax, using those parameters:
+
+    pyupgrade --keep-percent-format --py37-plus
+
+There is .pre-commit-config.yaml to use pre-commit to automatically run black,
+isort and pyupgrade before commits. (execute `pre-commit install` to install
+the git hook.)
+
 Remarks
 =======
 
diff --git a/mellon/adapters.py b/mellon/adapters.py
index 6ec5f80..ee95a2f 100644
--- a/mellon/adapters.py
+++ b/mellon/adapters.py
@@ -13,33 +13,29 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
-from xml.etree import ElementTree as ET
 import hashlib
-
 import logging
 import os
 import threading
 import time
 import uuid
+from xml.etree import ElementTree as ET
 
 import lasso
 import requests
 import requests.exceptions
 from atomicwrites import atomic_write
-
-from django.core.exceptions import PermissionDenied, FieldDoesNotExist
-from django.core.files.storage import default_storage
-from django.contrib import auth
+from django.contrib import auth, messages
 from django.contrib.auth.models import Group
-from django.contrib import messages
+from django.core.exceptions import FieldDoesNotExist, PermissionDenied
+from django.core.files.storage import default_storage
 from django.utils import six
 from django.utils.encoding import force_text
 from django.utils.six.moves.urllib.parse import urlparse
 from django.utils.translation import ugettext as _
 
-from . import utils, app_settings, models
+from . import app_settings, models, utils
 
 User = auth.get_user_model()
 
@@ -51,7 +47,7 @@ class UserCreationError(Exception):
 
 
 def display_truncated_list(l, max_length=10):
-    s = '[' + ', '.join(map(six.text_type, l))
+    s = '[' + ', '.join(map(str, l))
     if len(l) > max_length:
         s += '..truncated more than %d items (%d)]' % (max_length, len(l))
     else:
@@ -59,7 +55,7 @@ def display_truncated_list(l, max_length=10):
     return s
 
 
-class DefaultAdapter(object):
+class DefaultAdapter:
     def __init__(self, request=None):
         self.request = request
 
@@ -153,7 +149,7 @@ class DefaultAdapter(object):
                         idp['METADATA'] = fd.read()
                     # use file cache mtime as last_update time, prevent too many loading from different workers
                     last_update = max(last_update, os.stat(file_cache_path).st_mtime)
-                except (IOError, OSError):
+                except OSError:
                     warning('metadata url %s : error when loading the file cache %s', url, file_cache_path)
 
         # fresh cache, skip loading
@@ -305,7 +301,7 @@ class DefaultAdapter(object):
         if saml_attributes['name_id_format'] == lasso.SAML2_NAME_IDENTIFIER_FORMAT_TRANSIENT:
             if transient_federation_attribute and saml_attributes.get(transient_federation_attribute):
                 name_id = saml_attributes[transient_federation_attribute]
-                if not isinstance(name_id, six.string_types):
+                if not isinstance(name_id, str):
                     if len(name_id) == 1:
                         name_id = name_id[0]
                     else:
diff --git a/mellon/app_settings.py b/mellon/app_settings.py
index 82361ad..a177abf 100644
--- a/mellon/app_settings.py
+++ b/mellon/app_settings.py
@@ -1,7 +1,7 @@
 import sys
 
 
-class AppSettings(object):
+class AppSettings:
     __PREFIX = 'MELLON_'
     __DEFAULTS = {
         'IDENTITY_PROVIDERS': [],
diff --git a/mellon/backends.py b/mellon/backends.py
index 025a2f3..668f8c5 100644
--- a/mellon/backends.py
+++ b/mellon/backends.py
@@ -13,7 +13,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
+
 import logging
 
 from django.contrib.auth.backends import ModelBackend
diff --git a/mellon/middleware.py b/mellon/middleware.py
index 5db67ac..0bcd59f 100644
--- a/mellon/middleware.py
+++ b/mellon/middleware.py
@@ -13,12 +13,11 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
-from django.utils.http import urlencode
 from django.http import HttpResponseRedirect
-from django.utils.deprecation import MiddlewareMixin
 from django.urls import reverse
+from django.utils.deprecation import MiddlewareMixin
+from django.utils.http import urlencode
 
 from . import app_settings, utils
 
diff --git a/mellon/migrations/0001_initial.py b/mellon/migrations/0001_initial.py
index ed281b4..2e04812 100644
--- a/mellon/migrations/0001_initial.py
+++ b/mellon/migrations/0001_initial.py
@@ -1,8 +1,5 @@
-# -*- coding: utf-8 -*-
-from __future__ import unicode_literals
-
-from django.db import models, migrations
 from django.conf import settings
+from django.db import migrations, models
 
 
 class Migration(migrations.Migration):
@@ -40,6 +37,6 @@ class Migration(migrations.Migration):
         ),
         migrations.AlterUniqueTogether(
             name='usersamlidentifier',
-            unique_together=set([('issuer', 'name_id')]),
+            unique_together={('issuer', 'name_id')},
         ),
     ]
diff --git a/mellon/migrations/0002_sessionindex.py b/mellon/migrations/0002_sessionindex.py
index 41d0309..5e5ebc4 100644
--- a/mellon/migrations/0002_sessionindex.py
+++ b/mellon/migrations/0002_sessionindex.py
@@ -1,7 +1,7 @@
 # Generated by Django 2.2.12 on 2020-04-24 05:14
 
-from django.db import migrations, models
 import django.db.models.deletion
+from django.db import migrations, models
 
 
 class Migration(migrations.Migration):
diff --git a/mellon/models.py b/mellon/models.py
index 755756b..740487c 100644
--- a/mellon/models.py
+++ b/mellon/models.py
@@ -13,13 +13,12 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
 from importlib import import_module
 
+from django.conf import settings
 from django.db import models
 from django.utils.translation import ugettext_lazy as _
-from django.conf import settings
 
 
 class UserSAMLIdentifier(models.Model):
diff --git a/mellon/sessions_backends/db.py b/mellon/sessions_backends/db.py
index a45eadf..dbec306 100644
--- a/mellon/sessions_backends/db.py
+++ b/mellon/sessions_backends/db.py
@@ -29,10 +29,10 @@ class SessionStore(SessionStore):
         session_not_on_or_after = self.get_session_not_on_or_after()
         if session_not_on_or_after and 'expiry' not in kwargs:
             kwargs['expiry'] = session_not_on_or_after
-        return super(SessionStore, self).get_expiry_age(**kwargs)
+        return super().get_expiry_age(**kwargs)
 
     def get_expiry_date(self, **kwargs):
         session_not_on_or_after = self.get_session_not_on_or_after()
         if session_not_on_or_after and 'expiry' not in kwargs:
             kwargs['expiry'] = session_not_on_or_after
-        return super(SessionStore, self).get_expiry_date(**kwargs)
+        return super().get_expiry_date(**kwargs)
diff --git a/mellon/urls.py b/mellon/urls.py
index dca25b5..0e44152 100644
--- a/mellon/urls.py
+++ b/mellon/urls.py
@@ -1,11 +1,8 @@
-from __future__ import unicode_literals
-
-from django.conf.urls import url
 import django
+from django.conf.urls import url
 
 from . import views
 
-
 urlpatterns = [
     url('login/$', views.login, name='mellon_login'),
     url('login/debug/$', views.debug_login, name='mellon_debug_login'),
diff --git a/mellon/utils.py b/mellon/utils.py
index 77bb899..a05fcae 100644
--- a/mellon/utils.py
+++ b/mellon/utils.py
@@ -13,23 +13,22 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
-import logging
 import datetime
 import importlib
+import logging
 from functools import wraps
-import isodate
 from xml.parsers import expat
 
+import isodate
+import lasso
+from django.conf import settings
 from django.contrib import auth
 from django.template.loader import render_to_string
 from django.urls import reverse
 from django.utils.encoding import force_text
-from django.utils.timezone import make_aware, now, make_naive, is_aware, get_default_timezone
-from django.conf import settings
 from django.utils.six.moves.urllib.parse import urlparse
-import lasso
+from django.utils.timezone import get_default_timezone, is_aware, make_aware, make_naive, now
 
 from . import app_settings
 
@@ -133,8 +132,7 @@ def get_idp(entity_id):
 def get_idps():
     for adapter in get_adapters():
         if hasattr(adapter, 'get_idps'):
-            for idp in adapter.get_idps():
-                yield idp
+            yield from adapter.get_idps()
 
 
 def flatten_datetime(d):
diff --git a/mellon/views.py b/mellon/views.py
index c78c517..aac7a75 100644
--- a/mellon/views.py
+++ b/mellon/views.py
@@ -13,53 +13,43 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
+import logging
+import uuid
+import xml.etree.ElementTree as ET
 from contextlib import contextmanager, nullcontext
 from importlib import import_module
 from io import StringIO
-import logging
-import requests
-import lasso
-import uuid
-from requests.exceptions import RequestException
 from xml.sax.saxutils import escape
-import xml.etree.ElementTree as ET
 
 import django.http
-from django.views.generic import View
-from django.views.generic.base import RedirectView
-from django.http import HttpResponseRedirect, HttpResponse, HttpResponseForbidden
-from django.contrib import auth
-from django.contrib.auth import get_user_model
+import lasso
+import requests
 from django.conf import settings
-from django.views.decorators.csrf import csrf_exempt
+from django.contrib import auth
+from django.contrib.auth import REDIRECT_FIELD_NAME, get_user_model
+from django.db import transaction
+from django.http import HttpResponse, HttpResponseForbidden, HttpResponseRedirect
 from django.shortcuts import render, resolve_url
 from django.urls import reverse
-from django.utils.http import urlencode
 from django.utils import six
-from django.utils.encoding import force_text, force_str
-from django.contrib.auth import REDIRECT_FIELD_NAME
-from django.db import transaction
+from django.utils.encoding import force_str, force_text
+from django.utils.http import urlencode
 from django.utils.translation import ugettext as _
+from django.views.decorators.csrf import csrf_exempt
+from django.views.generic import View
+from django.views.generic.base import RedirectView
+from requests.exceptions import RequestException
 
-from . import app_settings, utils, models
-
+from . import app_settings, models, utils
 
 RETRY_LOGIN_COOKIE = 'MELLON_RETRY_LOGIN'
 
 lasso.setFlag('thin-sessions')
 
-if six.PY3:
 
-    def lasso_decode(x):
-        return x
-
-
-else:
-
-    def lasso_decode(x):
-        return x.decode('utf-8')
+def lasso_decode(x):
+    return x
 
 
 EO_NS = 'https://www.entrouvert.com/'
@@ -71,16 +61,16 @@ User = get_user_model()
 class HttpResponseBadRequest(django.http.HttpResponseBadRequest):
     def __init__(self, *args, **kwargs):
         kwargs['content_type'] = kwargs.get('content_type', 'text/plain')
-        super(HttpResponseBadRequest, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
         self['X-Content-Type-Options'] = 'nosniff'
 
 
-class LogMixin(object):
+class LogMixin:
     """Initialize a module logger in new objects"""
 
     def __init__(self, *args, **kwargs):
         self.log = logging.getLogger(__name__)
-        super(LogMixin, self).__init__(*args, **kwargs)
+        super().__init__(*args, **kwargs)
 
 
 def check_next_url(request, next_url):
@@ -101,7 +91,7 @@ def check_next_url(request, next_url):
     return next_url
 
 
-class ProfileMixin(object):
+class ProfileMixin:
     profile = None
 
     def set_next_url(self, next_url):
@@ -507,7 +497,7 @@ class LoginView(ProfileMixin, LogMixin, View):
             # configure requested AuthnClassRef
             authn_classref = utils.get_setting(idp, 'AUTHN_CLASSREF')
             if authn_classref:
-                authn_classref = tuple([str(x) for x in authn_classref])
+                authn_classref = tuple(str(x) for x in authn_classref)
                 req_authncontext = lasso.Samlp2RequestedAuthnContext()
                 authn_request.requestedAuthnContext = req_authncontext
                 req_authncontext.authnContextClassRef = authn_classref
@@ -550,8 +540,7 @@ class LoginView(ProfileMixin, LogMixin, View):
         assert hasattr(authn_request.extensions, 'any'), 'extension nodes need lasso > 2.5.1'
         serialized = ET.tostring(node, 'utf-8')
         # tostring return bytes in PY3, but lasso needs str
-        if six.PY3:
-            serialized = serialized.decode('utf-8')
+        serialized = serialized.decode('utf-8')
         extension_content = authn_request.extensions.any or ()
         extension_content += (serialized,)
         authn_request.extensions.any = extension_content
@@ -653,7 +642,7 @@ class LogoutView(ProfileMixin, LogMixin, View):
             return HttpResponseBadRequest('error processing logout request: %r' % e)
 
         issuer = force_text(logout.remoteProviderId)
-        session_indexes = set(force_text(sessionIndex) for sessionIndex in logout.request.sessionIndexes)
+        session_indexes = {force_text(sessionIndex) for sessionIndex in logout.request.sessionIndexes}
 
         saml_identifier = (
             models.UserSAMLIdentifier.objects.filter(
diff --git a/setup.py b/setup.py
index 6fa8b1e..5a130b4 100755
--- a/setup.py
+++ b/setup.py
@@ -5,11 +5,12 @@
 
 import os
 import subprocess
-from setuptools import setup, find_packages
-from setuptools.command.install_lib import install_lib as _install_lib
-from distutils.command.build import build as _build
-from setuptools.command.sdist import sdist as _sdist
 from distutils.cmd import Command
+from distutils.command.build import build as _build
+
+from setuptools import find_packages, setup
+from setuptools.command.install_lib import install_lib as _install_lib
+from setuptools.command.sdist import sdist as _sdist
 
 
 class compile_translations(Command):
@@ -24,6 +25,7 @@ class compile_translations(Command):
 
     def run(self):
         import os
+
         from django.core.management import call_command
 
         os.environ.pop('DJANGO_SETTINGS_MODULE', None)
@@ -68,7 +70,7 @@ def get_version():
     tag exists, take 0.0.0- and add the length of the commit log.
     """
     if os.path.exists('VERSION'):
-        with open('VERSION', 'r') as v:
+        with open('VERSION') as v:
             return v.read()
     if os.path.exists('.git'):
         p = subprocess.Popen(
diff --git a/tests/conftest.py b/tests/conftest.py
index 882e300..2e668be 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -13,11 +13,11 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-import os
 import logging
+import os
 
-import pytest
 import django_webtest
+import pytest
 
 
 @pytest.fixture(autouse=True)
diff --git a/tests/test_default_adapter.py b/tests/test_default_adapter.py
index a8e3b4d..771c885 100644
--- a/tests/test_default_adapter.py
+++ b/tests/test_default_adapter.py
@@ -13,24 +13,21 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
 import datetime
 import re
-import lasso
 import time
 from multiprocessing.pool import ThreadPool
+from unittest import mock
 
-import mock
+import lasso
 import pytest
-
 from django.contrib import auth
 from django.db import connection
 
 from mellon.adapters import DefaultAdapter
 from mellon.backends import SAMLBackend
 
-
 pytestmark = pytest.mark.django_db
 
 User = auth.get_user_model()
@@ -119,7 +116,7 @@ def test_lookup_user_transaction(transactional_db, concurrency, idp, saml_attrib
     users = p.map(f, range(concurrency))
 
     assert len(users) == concurrency
-    assert len(set(user.pk for user in users)) == 1
+    assert len({user.pk for user in users}) == 1
 
 
 def test_provision_user_attributes(settings, django_user_model, idp, saml_attributes, caplog):
diff --git a/tests/test_sso_slo.py b/tests/test_sso_slo.py
index 61eae22..970d50c 100644
--- a/tests/test_sso_slo.py
+++ b/tests/test_sso_slo.py
@@ -13,32 +13,29 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
-import datetime
-from html import unescape
-import re
 import base64
-import zlib
+import datetime
+import re
 import xml.etree.ElementTree as ET
+import zlib
+from html import unescape
 
 import lasso
-
 import pytest
-from pytest import fixture
-
-from django.contrib.sessions.models import Session
 from django.contrib.auth.models import User
+from django.contrib.sessions.models import Session
 from django.urls import reverse
 from django.utils import six
-from django.utils.six.moves.urllib import parse as urlparse
 from django.utils.encoding import force_str
+from django.utils.six.moves.urllib import parse as urlparse
+from httmock import HTTMock, all_requests
+from httmock import response as mock_response
+from pytest import fixture
 
 from mellon.utils import create_metadata
 from mellon.views import lasso_decode
 
-from httmock import all_requests, HTTMock, response as mock_response
-
 
 @fixture
 def idp_metadata():
@@ -81,7 +78,7 @@ def sp_metadata(sp_settings, rf):
     return create_metadata(request)
 
 
-class MockIdp(object):
+class MockIdp:
     session_dump = None
     identity_dump = None
 
@@ -240,10 +237,10 @@ def test_sso_slo(db, app, idp, caplog, sp_settings):
     assert 'created new user' in caplog.text
     assert 'logged in using SAML' in caplog.text
     assert urlparse.urlparse(response['Location']).path == '/whatever/'
-    response = app.get(reverse('mellon_logout'), extra_environ={'HTTP_REFERER': str('/some/path')})
+    response = app.get(reverse('mellon_logout'), extra_environ={'HTTP_REFERER': '/some/path'})
     assert urlparse.urlparse(response['Location']).path == '/singleLogout'
     # again, user is already logged out
-    response = app.get(reverse('mellon_logout'), extra_environ={'HTTP_REFERER': str('/some/path')})
+    response = app.get(reverse('mellon_logout'), extra_environ={'HTTP_REFERER': '/some/path'})
     assert urlparse.urlparse(response['Location']).path == '/some/path'
 
 
@@ -433,18 +430,11 @@ def test_sso_request_denied(db, app, idp, caplog, sp_settings):
     assert not relay_state
     assert url.endswith(reverse('mellon_login'))
     response = app.post(reverse('mellon_login'), params={'SAMLResponse': body, 'RelayState': relay_state})
-    if six.PY3:
-        assert (
-            "status is not success codes: ['urn:oasis:names:tc:SAML:2.0:status:Responder',\
+    assert (
+        "status is not success codes: ['urn:oasis:names:tc:SAML:2.0:status:Responder',\
  'urn:oasis:names:tc:SAML:2.0:status:RequestDenied']"
-            in caplog.text
-        )
-    else:
-        assert (
-            "status is not success codes: [u'urn:oasis:names:tc:SAML:2.0:status:Responder',\
- u'urn:oasis:names:tc:SAML:2.0:status:RequestDenied']"
-            in caplog.text
-        )
+        in caplog.text
+    )
 
 
 @pytest.mark.urls('urls_tests_template_base')
@@ -663,7 +653,7 @@ def test_passive_auth_middleware_ok(db, app, idp, caplog, settings):
     settings.MELLON_OPENED_SESSION_COOKIE_NAME = 'IDP_SESSION'
     assert 'MELLON_PASSIVE_TRIED' not in app.cookies
     # webtest-lint is against unicode
-    app.set_cookie(str('IDP_SESSION'), str('1'))
+    app.set_cookie('IDP_SESSION', '1')
     response = app.get('/', headers={'Accept': force_str('text/html')}, status=302)
     assert urlparse.urlparse(response.location).path == '/login/'
     assert urlparse.parse_qs(urlparse.urlparse(response.location).query, keep_blank_values=True) == {
@@ -681,7 +671,7 @@ def test_passive_auth_middleware_ok(db, app, idp, caplog, settings):
     assert 'MELLON_PASSIVE_TRIED' not in app.cookies
 
     # check passive authentication is tried again
-    app.set_cookie(str('IDP_SESSION'), str('1'))
+    app.set_cookie('IDP_SESSION', '1')
     response = app.get('/', headers={'Accept': force_str('text/html')}, status=302)
     assert urlparse.urlparse(response.location).path == '/login/'
     assert urlparse.parse_qs(urlparse.urlparse(response.location).query, keep_blank_values=True) == {
@@ -695,7 +685,7 @@ def test_passive_auth_middleware_no_passive_auth_parameter(db, app, idp, caplog,
     settings.MELLON_OPENED_SESSION_COOKIE_NAME = 'IDP_SESSION'
     assert 'MELLON_PASSIVE_TRIED' not in app.cookies
     # webtest-lint is against unicode
-    app.set_cookie(str('IDP_SESSION'), str('1'))
+    app.set_cookie('IDP_SESSION', '1')
     app.get('/?no-passive-auth', headers={'Accept': force_str('text/html')}, status=200)
 
 
diff --git a/tests/test_utils.py b/tests/test_utils.py
index fb5fa21..d4f38cb 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -13,17 +13,16 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
 import datetime
+from unittest import mock
 
-import mock
 import lasso
-
-from mellon.utils import create_metadata, iso8601_to_datetime, flatten_datetime
-from mellon.views import check_next_url
 from xml_utils import assert_xml_constraints
 
+from mellon.utils import create_metadata, flatten_datetime, iso8601_to_datetime
+from mellon.views import check_next_url
+
 
 def test_create_metadata(rf, private_settings, caplog):
     ns = {
@@ -144,17 +143,17 @@ def test_flatten_datetime():
         'y': 1,
         'z': 'u',
     }
-    assert set(flatten_datetime(d).keys()) == set(['x', 'y', 'z'])
+    assert set(flatten_datetime(d).keys()) == {'x', 'y', 'z'}
     assert flatten_datetime(d)['x'] == '2010-10-10T10:10:34'
     assert flatten_datetime(d)['y'] == 1
     assert flatten_datetime(d)['z'] == 'u'
 
 
 def test_check_next_url(rf):
-    assert not check_next_url(rf.get('/'), u'')
+    assert not check_next_url(rf.get('/'), '')
     assert not check_next_url(rf.get('/'), None)
-    assert not check_next_url(rf.get('/'), u'\x00')
-    assert not check_next_url(rf.get('/'), u'\u010e')
-    assert not check_next_url(rf.get('/'), u'https://example.invalid/')
+    assert not check_next_url(rf.get('/'), '\x00')
+    assert not check_next_url(rf.get('/'), '\u010e')
+    assert not check_next_url(rf.get('/'), 'https://example.invalid/')
     # default hostname is testserver
-    assert check_next_url(rf.get('/'), u'http://testserver/ok/')
+    assert check_next_url(rf.get('/'), 'http://testserver/ok/')
diff --git a/tests/test_views.py b/tests/test_views.py
index 451709e..3783ce4 100644
--- a/tests/test_views.py
+++ b/tests/test_views.py
@@ -13,23 +13,20 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from __future__ import unicode_literals
 
-import pytest
-import mock
-import lasso
-from django.utils.six.moves.urllib.parse import parse_qs, urlparse
 import base64
 import hashlib
-from httmock import HTTMock
+from unittest import mock
 
+import lasso
+import pytest
 from django.urls import reverse
 from django.utils.encoding import force_text
 from django.utils.http import urlencode
-
-from xml_utils import assert_xml_constraints
-
+from django.utils.six.moves.urllib.parse import parse_qs, urlparse
+from httmock import HTTMock
 from utils import error_500, html_response
+from xml_utils import assert_xml_constraints
 
 pytestmark = pytest.mark.django_db
 
@@ -207,7 +204,7 @@ def test_sp_initiated_login(private_settings, client):
     assert response.status_code == 302
     params = parse_qs(urlparse(response['Location']).query)
     assert response['Location'].startswith('http://idp5/singleSignOn?')
-    assert set(params.keys()) == set(['SAMLRequest', 'RelayState'])
+    assert set(params.keys()) == {'SAMLRequest', 'RelayState'}
     assert len(params['SAMLRequest']) == 1
     assert base64.b64decode(params['SAMLRequest'][0])
     assert client.session['mellon_next_url_%s' % params['RelayState'][0]] == '/whatever'
@@ -229,7 +226,7 @@ def test_sp_initiated_login_chosen(private_settings, client):
     assert response.status_code == 302
     params = parse_qs(urlparse(response['Location']).query)
     assert response['Location'].startswith('http://idp5/singleSignOn?')
-    assert set(params.keys()) == set(['SAMLRequest', 'RelayState'])
+    assert set(params.keys()) == {'SAMLRequest', 'RelayState'}
     assert len(params['SAMLRequest']) == 1
     assert base64.b64decode(params['SAMLRequest'][0])
     assert client.session['mellon_next_url_%s' % params['RelayState'][0]] == '/whatever'
diff --git a/tests/urls_tests.py b/tests/urls_tests.py
index 16e7602..233848c 100644
--- a/tests/urls_tests.py
+++ b/tests/urls_tests.py
@@ -13,7 +13,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from django.conf.urls import url, include
+from django.conf.urls import include, url
 from django.http import HttpResponse
 
 
diff --git a/tests/urls_tests_template_base.py b/tests/urls_tests_template_base.py
index 8279af0..d800036 100644
--- a/tests/urls_tests_template_base.py
+++ b/tests/urls_tests_template_base.py
@@ -13,7 +13,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from django.conf.urls import url, include
+from django.conf.urls import include, url
 from django.http import HttpResponse
 
 
diff --git a/tests/urls_tests_template_hook.py b/tests/urls_tests_template_hook.py
index 0301d63..716c4d9 100644
--- a/tests/urls_tests_template_hook.py
+++ b/tests/urls_tests_template_hook.py
@@ -13,7 +13,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-from django.conf.urls import url, include
+from django.conf.urls import include, url
 from django.http import HttpResponse
 
 
diff --git a/testsettings.py b/testsettings.py
index 99e1726..104e585 100644
--- a/testsettings.py
+++ b/testsettings.py
@@ -1,4 +1,5 @@
 import os
+
 import django
 from django.conf import global_settings
 
diff --git a/tox.ini b/tox.ini
index 1c71d1c..4b137b8 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = black,py3-django22-coverage
+envlist = code-style,py3-django22-coverage
 toxworkdir = {env:TMPDIR:/tmp}/tox-{env:USER}/django-mellon/
 
 [testenv]
@@ -55,12 +55,12 @@ commands =
   ./getlasso3.sh
   django-admin {posargs:--help}
 
-[testenv:black]
+[testenv:code-style]
 skip_install = true
 deps =
   pre-commit
 commands =
-  pre-commit run black --all-files --show-diff-on-failure
+  pre-commit run --all-files --show-diff-on-failure
 
 [pytest]
 junit_family=legacy