docs: def unsubscribe(request, message_id, dispatch_id, hashed, redirect_to=None):
      """Handles unsubscribe request.
  
      :param Request request:
      :param int message_id:
      :param int dispatch_id:
      :param str hashed:
      :param str redirect_to:
      :return:
      """
      return _generic_view(
          'handle_unsubscribe_request', sig_unsubscribe_failed,
          request, message_id, dispatch_id, hashed, redirect_to=redirect_to
      )