diff --git a/backend/oj/settings.py b/backend/oj/settings.py
index 1eab17cd4..0ab778eb9 100644
--- a/backend/oj/settings.py
+++ b/backend/oj/settings.py
@@ -49,7 +49,7 @@
     'judge',
     'assignment',
     'course',
-    'group'
+    'group',
     'qna'
 ]