public static function get_analysis_returns() {
        return new external_single_structure(
            array(
            'completedcount' => new external_value(PARAM_INT, 'Number of completed submissions.'),
            'itemscount' => new external_value(PARAM_INT, 'Number of items (questions).'),
            'itemsdata' => new external_multiple_structure(
                new external_single_structure(
                    array(
                        'item' => feedback_item_exporter::get_read_structure(),
                        'data' => new external_multiple_structure(
                            new external_value(PARAM_RAW, 'The analysis data (can be json encoded)')
                        ),
                    )
                )
            ),
            'warnings' => new external_warnings(),
            )
        );
    }