code: func (members Members) ByID() map[string]NetworkMember {
  	res := make(map[string]NetworkMember, len(members))
  	for _, peer := range members {
  		res[string(peer.PKIid)] = peer
  	}
  	return res
  }
docs: // ByID returns a mapping from the PKI-IDs (in string form)
  // to NetworkMember