Fatal error: Uncaught Error: Interface "Symfony\Component\Serializer\Mapping\Loader\LoaderInterface" not found in I:\www\picman\vendor\symfony\serializer\Mapping\Loader\AttributeLoader.php:34 Stack trace: #0 {main} thrown in I:\www\picman\vendor\symfony\serializer\Mapping\Loader\AttributeLoader.php on line 34