Update migration to use User model explicitly

apps/accounts/migrations/0053_provider_permissions.py

@@ -12,16 +12,17 @@ def assign_object_permissions(apps, schema_editor):
     Assign object-level permissions for existing Hostingprovider and Datacenter objects
     """
     db_alias = schema_editor.connection.alias
+    User = get_user_model()
 
     # assign manage_datacenter
     Datacenter = apps.get_model("accounts", "Datacenter")
 
     for dc in Datacenter.objects.using(db_alias).filter(user__isnull=False).iterator():
-        assign_perm(permissions.manage_datacenter.codename, dc.user, dc)
+        user = User.objects.using(db_alias).get(id=dc.user.id)
+        assign_perm(permissions.manage_datacenter.codename, user, dc)
 
     # assign manage_provider
     # GOTCHA: catch a FieldError so that this migration does not fail when execued by a test runner
-    User = get_user_model()
     try:
         for user in (
             User.objects.using(db_alias)
@@ -40,15 +41,17 @@ def remove_object_permissions(apps, schema_editor):
     Remove object-level permissions for existing Hostingprovider and Datacenter objects
     """
     db_alias = schema_editor.connection.alias
+    User = get_user_model()
 
     # remove manage_datacenter
     Datacenter = apps.get_model("accounts", "Datacenter")
     for dc in Datacenter.objects.using(db_alias).filter(user__isnull=False).iterator():
-        remove_perm(permissions.manage_datacenter.codename, dc.user, dc)
+        user = User.objects.using(db_alias).get(id=dc.user.id)
+        remove_perm(permissions.manage_datacenter.codename, user, dc)
 
     # remove manage_provider
     # GOTCHA: catch a FieldError so that this migration does not fail when execued by a test runner
-    User = get_user_model()
+
     try:
         for user in (
             User.objects.using(db_alias)