public function get_handler()
    {
        $handler = new PrettyPageHandler();
            
        $handler->addDataTableCallback('$wp_query', [$this, 'add_query']);

        $handler->addDataTableCallback('$post', [$this, 'add_post']);

        $handler->addDataTableCallback('$wp', [$this, 'add_wp']);

        return $handler;
    }