Sort by featured

Hi

I would like to set Featured as default sort and found this

Sort by featured

/**
* Set to show ‘Featured’ first.
*
* @param WP_Query Object $wp_obj
* @return WP_Query Object $wp_obj
*/
function _custom_sort($wp_obj){
$wp_obj->set(‘meta_key’, ‘featured’);
$wp_obj->set(‘orderby’, ‘DESC’);
return $wp_obj;
}
add_filter( ‘pre_get_posts’, ‘_custom_sort’);

But if I use this code, only the featured entries are shown