Fatal error: Uncaught Error: Class 'core_external\external_api' not found in /home/elearningunmaha/public_html/grade/classes/external/get_groups_for_search_widget.php:37 Stack trace: #0 {main} thrown in /home/elearningunmaha/public_html/grade/classes/external/get_groups_for_search_widget.php on line 37