code: func (d Delivery) Reject(requeue bool) error {
  	if d.Acknowledger == nil {
  		return errDeliveryNotInitialized
  	}
  	return d.Acknowledger.Reject(d.DeliveryTag, requeue)
  }
docs: /*
  Reject delegates a negatively acknowledgement through the Acknowledger interface.
  
  When requeue is true, queue this message to be delivered to a consumer on a
  different channel.  When requeue is false or the server is unable to queue this
  message, it will be dropped.
  
  If you are batch processing deliveries, and your server supports it, prefer
  Delivery.Nack.
  
  Either Delivery.Ack, Delivery.Reject or Delivery.Nack must be called for every
  delivery that is not automatically acknowledged.
  */