code: func (consumer *Consumer) GetUnacked() (*Package, error) {
  	if !consumer.HasUnacked() {
  		return nil, fmt.Errorf("no unacked Packages found")
  	}
  	answer := consumer.Queue.redisClient.LIndex(
  		consumerWorkingQueueKey(consumer.Queue.Name, consumer.Name),
  		-1,
  	)
  	return consumer.parseRedisAnswer(answer)
  }
docs: // GetUnacked returns a single packages from the working queue of this consumer