Removed unnecessary parens in _get_app_label_and_model_name().

django/db/migrations/state.py

@@ -20,7 +20,7 @@ from .exceptions import InvalidBasesError
 def _get_app_label_and_model_name(model, app_label=''):
     if isinstance(model, str):
         split = model.split('.', 1)
-        return (tuple(split) if len(split) == 2 else (app_label, split[0]))
+        return tuple(split) if len(split) == 2 else (app_label, split[0])
     else:
         return model._meta.app_label, model._meta.model_name