How to Hide the "Updates Options" Admin Menu

function plt_hide_stops_core_theme_and_plugin_updates_menus() {
	//Hide the "Dashboard → Updates Options" menu.
	remove_submenu_page('index.php', 'mpsum-update-options');
}

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

Where do I put this code?