python 3 fixes

quality fixes

python 3 fixes

quality fixes

openedx/core/djangoapps/util/user_utils.py

@@ -3,12 +3,11 @@ Custom user-related utility code.
 """
 from __future__ import absolute_import
 
-import six
-
+from django.utils.encoding import python_2_unicode_compatible
 from django.contrib.auth.models import AnonymousUser
 
 
-@six.python_2_unicode_compatible
+@python_2_unicode_compatible
 class SystemUser(AnonymousUser):
     """
     A User that can act on behalf of system actions, when a user object is
@@ -17,6 +16,7 @@ class SystemUser(AnonymousUser):
     Like the AnonymousUser, this User is not represented in the database, and
     has no primary key.
     """
+
     # pylint: disable=abstract-method
     def __str__(self):
-        return u'SystemUser'
+        return 'SystemUser'