Fix query

aleksis/apps/alsijil/model_extensions.py

@@ -103,8 +103,8 @@ def annotate_person_statistics_for_school_term(
     )
     if group:
         documentations = documentations.filter(
-            pk__in=Documentation.objects.filter(course__groups=group).union(
-                Documentation.objects.filter(course__groups__parent_groups=group)
+            pk__in=Documentation.objects.filter(course__groups=group).values_list("pk", flat=True).union(
+                Documentation.objects.filter(course__groups__parent_groups=group).values_list("pk", flat=True)
             )
         )
     docs = list(documentations.values_list("pk", flat=True))