In wordpress add page attribute to custom post type -

i have created custom post type project , want add custom post type page attribute. have done following code:

function register_pt_boutique()  {      register_post_type('boutique', array(          'label'           => 'boutiques',          'description'     => 'this post type represents featured items on homepage.',          'public'          => true,          'show_ui'         => true,          'show_in_menu'    => true,          'capability_type' => 'post',          'map_meta_cap'    => true,          'hierarchical'    => true,          // 'rewrite' => array('slug' => 'featured', 'hierarchical' => true, 'with_front' => false),          'query_var'       => true,          'has_archive'     => true,          'menu_position'   => '7',          'supports'        => array('title', 'page-attributes','thumbnail'),          // 'taxonomies' => array('page-attributes'),          'labels'          => array(              'name'               => 'boutiques',              'singular_name'      => 'boutique',              'menu_name'          => 'boutiques',              'add_new'            => 'add boutique',              'add_new_item'       => 'add new boutique',              'edit'               => 'edit',              'edit_item'          => 'edit boutique',              'new_item'           => 'new boutique',              'view'               => 'view boutique',              'view_item'          => 'view boutique',              'search_items'       => 'search boutique',              'not_found'          => 'no boutique',              'not_found_in_trash' => 'no boutique found in trash',              'parent'             => 'parent boutique',          )      ));  }

using code page attribute option come 2 fields ("parent" , "order") @ admin side without "template" field option. want page attribute "template" field.

from wordpress 4.7 can include field "template" directly de file https://make.wordpress.org/core/2016/11/03/post-type-templates-in-4-7/