docs: def enabled(self):
          """Returns True if this notification is enabled based on the value
          of Notification model instance.
  
          Note: Notification names/display_names are persisted in the
          "Notification" model where each mode instance can be flagged
          as enabled or not, and are selected/subscribed to by
          each user in their user profile.
  
          See also: `site_notifications.update_notification_list`
          """
          if not self._notification_enabled:
              self._notification_enabled = self.notification_model.enabled
          return self._notification_enabled