code: func splitHostPort(host string) (string, string) {
  	ix := strings.LastIndex(host, ":")
  
  	if ix <= strings.LastIndex(host, "]") {
  		return host, ""
  	}
  
  	name := host[:ix]
  	port := host[ix+1:]
  
  	return name, port
  }
docs: // splitHostPort is similar to net.SplitHostPort,
  // but rather than return error if there isn't a ':port',
  // return an empty string for the port.