Notice: Undefined variable: container in C:\xampp\htdocs\ITI\uvdesk\vendor\symfony\framework-bundle\Tests\DependencyInjection\Fixtures\php\serializer_mapping.php on line 3

Fatal error: Uncaught Error: Call to a member function loadFromExtension() on null in C:\xampp\htdocs\ITI\uvdesk\vendor\symfony\framework-bundle\Tests\DependencyInjection\Fixtures\php\serializer_mapping.php:3 Stack trace: #0 {main} thrown in C:\xampp\htdocs\ITI\uvdesk\vendor\symfony\framework-bundle\Tests\DependencyInjection\Fixtures\php\serializer_mapping.php on line 3