Fatal error: Uncaught Error: Class "Symfony\Bundle\FrameworkBundle\CacheWarmer\AbstractPhpFileCacheWarmer" not found in /home/ldt/public_html/canvas/udoit/vendor/symfony/framework-bundle/CacheWarmer/SerializerCacheWarmer.php:28 Stack trace: #0 {main} thrown in /home/ldt/public_html/canvas/udoit/vendor/symfony/framework-bundle/CacheWarmer/SerializerCacheWarmer.php on line 28