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Fatal error: Uncaught Error: Class 'yii\helpers\Html' not found in /var/www/html/forms_dir/vendor/yiisoft/yii2-gii/src/generators/extension/form.php:9 Stack trace: #0 {main} thrown in /var/www/html/forms_dir/vendor/yiisoft/yii2-gii/src/generators/extension/form.php on line 9