public static function setBaseHeaders($token, $userAgent)
    {
        return Middleware::mapRequest(
            function (Request $request) use ($token, $userAgent) {
                return $request->withHeader('Accept', 'application/json')
                               ->withHeader('Authorization', 'Bearer '.$token)
                               ->withHeader('User-Agent', $userAgent);
            }
        );
    }