code: func createRegistry(urls string) (*node.EtcdRegistry, error) {
  	ectdEndpoints, err := utils.ParseHostPortAddr(urls)
  	if err != nil {
  		return nil, errors.Trace(err)
  	}
  	cli, err := etcd.NewClientFromCfg(ectdEndpoints, etcdDialTimeout, node.DefaultRootPath, nil)
  	if err != nil {
  		return nil, errors.Trace(err)
  	}
  
  	return node.NewEtcdRegistry(cli, etcdDialTimeout), nil
  }
docs: // createRegistry returns an ectd registry