Fixed #21868: Don't die when seeing py3 namespace packages for mig dirs

django/db/migrations/questioner.py

@@ -39,7 +39,12 @@ class MigrationQuestioner(object):
         except ImportError:
             return self.defaults.get("ask_initial", False)
         else:
-            filenames = os.listdir(os.path.dirname(migrations_module.__file__))
+            if hasattr(migrations_module, "__file__"):
+                filenames = os.listdir(os.path.dirname(migrations_module.__file__))
+            elif hasattr(migrations_module, "__path__"):
+                if len(migrations_module.__path__) > 1:
+                    return False
+                filenames = os.listdir(list(migrations_module.__path__)[0])
             return not any(x.endswith(".py") for x in filenames if x != "__init__.py")
 
     def ask_not_null_addition(self, field_name, model_name):