code: static function getStringFromHTTPStatusCode($httpStatusCode)
      {
          if (array_key_exists($httpStatusCode, HTTPResponseCodes::$codes) === true) {
              return HTTPResponseCodes::$codes[$httpStatusCode];
          } else {
              return "unknown error code: " . $httpStatusCode;
          }
      }
docs: Maps a numeric HTTP status code to the corresponding string message.
  
  @param number $httpStatusCode
  the HTTP status code to translate
  @return string
  the corresponding string message, or an error message if the status code is unkown