public function getResponse($deflate = null)
    {
        $subject = $this->_logoutResponse;

        if (is_null($deflate)) {
            $deflate = $this->_settings->shouldCompressResponses();
        }

        if ($deflate) {
            $subject = gzdeflate($this->_logoutResponse);
        }
        return base64_encode($subject);
    }