public static function finish_attempt_parameters() {
        return new external_function_parameters (
            array(
                'lessonid' => new external_value(PARAM_INT, 'Lesson instance id.'),
                'password' => new external_value(PARAM_RAW, 'Optional password (the lesson may be protected).', VALUE_DEFAULT, ''),
                'outoftime' => new external_value(PARAM_BOOL, 'If the user run out of time.', VALUE_DEFAULT, false),
                'review' => new external_value(PARAM_BOOL, 'If we want to review just after finishing (1 hour margin).',
                    VALUE_DEFAULT, false),
            )
        );
    }