code: def handle_unsubscribe_request(cls, request, message, dispatch, hash_is_valid, redirect_to):
          
  
          if hash_is_valid:
              Subscription.cancel(
                  dispatch.recipient_id or dispatch.address, cls.alias, dispatch.messenger
              )
              signal = sig_unsubscribe_success
          else:
              signal = sig_unsubscribe_failed
  
          signal.send(cls, request=request, message=message, dispatch=dispatch)
          return redirect(redirect_to)
docs: Handles user subscription cancelling request.
  
          :param Request request: Request instance
          :param Message message: Message model instance
          :param Dispatch dispatch: Dispatch model instance
          :param bool hash_is_valid: Flag indicating that user supplied request signature is correct
          :param str redirect_to: Redirection URL
          :rtype: list