code: func (lbp *RoundRobin) Choose(peers []fab.Peer) (fab.Peer, error) {
  	if len(peers) == 0 {
  		logger.Warn("No peers to choose from!")
  		return nil, nil
  	}
  	return peers[lbp.counter.Next(len(peers))], nil
  }
docs: // Choose chooses from the list of peers in round-robin fashion