diff --git a/tests/test_serializer_lists.py b/tests/test_serializer_lists.py
index 732a1fb6f..9cc2f7eaa 100644
--- a/tests/test_serializer_lists.py
+++ b/tests/test_serializer_lists.py
@@ -6,7 +6,7 @@ from django.utils.datastructures import MultiValueDict
 
 from rest_framework import serializers
 from rest_framework.exceptions import ErrorDetail
-from tests.models import (
+from tests.models import (CustomManagerModel, NullableOneToOneSource, OneToOneTarget)
     CustomManagerModel,
     NullableOneToOneSource,
     OneToOneTarget