httputil/response.go
func ResponseStatus(w http.ResponseWriter) int {
	return int(httpResponseStruct(reflect.ValueOf(w)).FieldByName("status").Int())
}
func ResponseStatus(w http.ResponseWriter) int {
	return int(httpResponseStruct(reflect.ValueOf(w)).FieldByName("status").Int())
}
// ResponseStatus returns the HTTP response status.
// Remember that the status is only set by the server after WriteHeader has been called.