public static function upload_course_backup($hubcourseid, \stored_file $backupfile) {
        $curl = new \curl();
        $params = array();
        $params['filetype'] = self::HUB_BACKUP_FILE_TYPE;
        $params['courseid'] = $hubcourseid;
        $params['file'] = $backupfile;
        $params['token'] = registration::get_token();
        $curl->post(HUB_MOODLEORGHUBURL . '/local/hub/webservice/upload.php', $params);
    }