How to Hide the "Debug Objects" Admin Menu

function plt_hide_debug_objects_menus() {
	//Hide the "Tools → Debug Objects" menu.
	remove_submenu_page('tools.php', 'debug-objects/inc/autoload/class-settings.php');
}

add_action('admin_menu', 'plt_hide_debug_objects_menus', 11);

Where do I put this code?