code: func NewPeerClientForAddress(address, tlsRootCertFile string) (*PeerClient, error) {
  	if address == "" {
  		return nil, errors.New("peer address must be set")
  	}
  
  	_, override, clientConfig, err := configFromEnv("peer")
  	if clientConfig.SecOpts.UseTLS {
  		if tlsRootCertFile == "" {
  			return nil, errors.New("tls root cert file must be set")
  		}
  		caPEM, res := ioutil.ReadFile(tlsRootCertFile)
  		if res != nil {
  			err = errors.WithMessage(res, fmt.Sprintf("unable to load TLS root cert file from %s", tlsRootCertFile))
  			return nil, err
  		}
  		clientConfig.SecOpts.ServerRootCAs = [][]byte{caPEM}
  	}
  	return newPeerClientForClientConfig(address, override, clientConfig)
  }
docs: // NewPeerClientForAddress creates an instance of a PeerClient using the
  // provided peer address and, if TLS is enabled, the TLS root cert file