Fatal error: Uncaught Error: Call to undefined function sanitize_key() in /home/lextgwtg/homeworks.ng/wp-content/plugins/tutor/views/options/field-types/select.php:13 Stack trace: #0 {main} thrown in /home/lextgwtg/homeworks.ng/wp-content/plugins/tutor/views/options/field-types/select.php on line 13