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Warning: foreach() argument must be of type array|object, null given in /mnt/disk1/hosted/cuadro_mando/vendor/yiisoft/yii2/views/_addColumns.php on line 1

Fatal error: Uncaught Error: Using $this when not in object context in /mnt/disk1/hosted/cuadro_mando/vendor/yiisoft/yii2/views/_addColumns.php:11 Stack trace: #0 {main} thrown in /mnt/disk1/hosted/cuadro_mando/vendor/yiisoft/yii2/views/_addColumns.php on line 11