Copy standard Django practice

Author: AlanCoding

ansible_base/resource_registry/fields.py

@@ -14,10 +14,12 @@ def get_queryset(self, **hints):
         return self.field.remote_field.model._base_manager.db_manager(hints=hints).filter(content_type=ContentType.objects.get_for_model(self.field.model))
 
     def get_prefetch_querysets(self, instances, querysets=None):
-        if not querysets:
-            queryset = self.get_queryset()
-        else:
-            queryset = querysets[0]
+        if querysets and len(querysets) != 1:
+            raise ValueError(
+                "querysets argument of get_prefetch_querysets() should have a length "
+                "of 1."
+            )
+        queryset = querysets[0] if querysets else self.get_queryset()
         queryset._add_hints(instance=instances[0])
 
         query = models.Q.create(