code: func GetLatencyForURL(addr string) (time.Duration, error) {
  	uri, err := url.Parse(addr)
  	if err != nil {
  		return 0, err
  	}
  
  	return TCPPing(uri.Host)
  }
docs: // GetLatencyForURL parses the given URL, tries opening a TCP connection to it
  // and returns the time it took to establish the connection.