code: public function get($key, $default = null)
      {
          return ArrayHelper::getValue(
              $this->parsedResponse,
              sprintf('%s.%s', self::RESPONSE_DATA_PARAM, $key),
              $default
          );
      }
docs: Gets the value of key if key exists, default value otherwise
  @author Adegoke Obasa <goke@cottacush.com>
  @param $key
  @param null $default
  @return mixed