code: func (subs *consumers) send(tag string, msg *Delivery) bool {
  	subs.Lock()
  	defer subs.Unlock()
  
  	buffer, found := subs.chans[tag]
  	if found {
  		buffer <- msg
  	}
  
  	return found
  }
docs: // Sends a delivery to a the consumer identified by `tag`.
  // If unbuffered channels are used for Consume this method
  // could block all deliveries until the consumer
  // receives on the other end of the channel.