Fatal error: Uncaught Error: Class 'Doctrine\Common\DataFixtures\Loader' not found in D:\workspaces\liZiPingBack\vendor\symfony\doctrine-bridge\DataFixtures\ContainerAwareLoader.php:26 Stack trace: #0 {main} thrown in D:\workspaces\liZiPingBack\vendor\symfony\doctrine-bridge\DataFixtures\ContainerAwareLoader.php on line 26