public function createResponse($content = null, array $headers = [])
    {
        $config = $this->responseConfig;
        if (!isset($config['class'])) {
            $config['class'] = Response::className();
        }
        $config['client'] = $this;
        $response = Yii::createObject($config);
        $response->setContent($content);
        $response->setHeaders($headers);
        return $response;
    }