code: def nack(self, delivery_tag, multiple=False, requeue=False):
          '''Send a nack to the broker.'''
          args = Writer()
          args.write_longlong(delivery_tag).\
              write_bits(multiple, requeue)
  
          self.send_frame(MethodFrame(self.channel_id, 60, 120, args)f nack(self, delivery_tag, multiple=False, requeue=False):
          '''Send a nack to the broker.'''
          args = Writer()
          args.write_longlong(delivery_tag).\
              write_bits(multiple, requeue)
  
          self.send_frame(MethodFrame(self.channel_id, 60, 120, args))
docs: Send a nack to the broker.