Fatal error: Uncaught Error: Class "core\external\persistent_exporter" not found in C:\Apache24\htdocs\moodle\reportbuilder\classes\external\custom_report_details_exporter.php:36 Stack trace: #0 {main} thrown in C:\Apache24\htdocs\moodle\reportbuilder\classes\external\custom_report_details_exporter.php on line 36