remove update from wordpress

/*&
     *@Disable auto update plugn and themes and wordpress version
     */
   
    add_action('after_setup_theme','remove_core_updates');
    function remove_core_updates()
    {
    if(! current_user_can('update_core')){return;}
    add_action('init', create_function('$a',"remove_action( 'init', 'wp_version_check' );"),2);
    add_filter('pre_option_update_core','__return_null');
    add_filter('pre_site_transient_update_core','__return_null');
    }

    remove_action('load-update-core.php','wp_update_plugins');
    add_filter('pre_site_transient_update_plugins','__return_null');