/**
     * create construct method.
     * @return object
     */
    private static function getCall() {
      try {
        $mailchimp = new MailchimpMarketing\ApiClient();
        $mailchimp->setConfig([
            'apiKey' => env('MAILCHIMP_API_KEY'),
            'server' => env('MAILCHIMP_SERVER')
        ]);
      } catch (Exception $e) {
        return array('error' => true, 'error_message' => $e->getMessage());
      }

      return $mailchimp;
    }