docs: def is_restricted(self):
          """
          Returns True or False according to number of objects in queryset.
          If queryset contains too much objects the widget will be restricted and won't be used select box with choices.
          """
          return (
              not hasattr(self.choices, 'queryset') or
              self.choices.queryset.count() > settings.FOREIGN_KEY_MAX_SELECBOX_ENTRIES
          )