code: func Error(w http.ResponseWriter, err error, status int) error {
  	res := newError(err)
  
  	// If the ErrorResource provides and exit status, we'll use that
  	// instead.
  	if res.Status != 0 {
  		status = res.Status
  	}
  
  	w.WriteHeader(status)
  	return Encode(w, res)
  }
docs: // Error is used to respond with errors in the heroku error format, which is
  // specified at
  // https://devcenter.heroku.com/articles/platform-api-reference#errors
  //
  // If an ErrorResource is provided as the error, and it provides a non-zero
  // status, that will be used as the response status code.