code: func SafeForLoggingURL(input string) (string, error) {
  	u, err := url.Parse(input)
  	if err != nil {
  		return input, err
  	}
  	if u.User == nil {
  		return input, nil
  	}
  	if _, passwordSet := u.User.Password(); passwordSet {
  		// wipe out the user info from the url.
  		u.User = url.User("redacted")
  	}
  	return u.String(), nil
  }
docs: // SafeForLoggingURL removes the user:password section of
  // a url if present.  If not present or the value is unparseable,
  // the value is returned unchanged.