code: def recover(self, requeue=False, cb=None):
          '''
          Ask server to redeliver all unacknowledged messages.
          '''
          args = Writer()
          args.write_bit(requeue)
  
          # The XML spec is incorrect; this method is always synchronous
          #  http://lists.rabbitmq.com/pipermail/rabbitmq-discuss/2011-January/010738.html
          self._recover_cb.append(cb)
          self.send_frame(MethodFrame(self.channel_id, 60, 110, args))
          self.channel.add_synchronous_cb(self._recv_recover_okf recover(self, requeue=False, cb=None):
          '''
          Ask server to redeliver all unacknowledged messages.
          '''
          args = Writer()
          args.write_bit(requeue)
  
          # The XML spec is incorrect; this method is always synchronous
          #  http://lists.rabbitmq.com/pipermail/rabbitmq-discuss/2011-January/010738.html
          self._recover_cb.append(cb)
          self.send_frame(MethodFrame(self.channel_id, 60, 110, args))
          self.channel.add_synchronous_cb(self._recv_recover_ok)
docs: Ask server to redeliver all unacknowledged messages.