python3: deprecate django.utils.encoding.smart_unicode (#31155)

src/authentic2/idp/saml/saml2_endpoints.py

@@ -54,7 +54,7 @@ from django.views.decorators.cache import never_cache
 from django.views.decorators.http import require_POST
 from django.contrib.auth import BACKEND_SESSION_KEY, REDIRECT_FIELD_NAME
 from django.conf import settings
-from django.utils.encoding import smart_unicode
+from django.utils.encoding import force_text
 from django.utils.six.moves.urllib.parse import quote, urlencode
 from django.contrib.auth import load_backend
 from django.shortcuts import render, redirect
@@ -318,7 +318,7 @@ def saml2_add_attribute_values(assertion, attributes):
                     elif value is False:
                         value = u'false'
                     else:
-                        value = smart_unicode(value)
+                        value = force_text(value)
                     value = value.encode('utf-8')
                     text_node = lasso.MiscTextNode.newWithString(value)
                     text_node.textChild = True