How to Hide the "Export All URLs" Admin Menu

function plt_hide_export_all_urls_menus() {
	//Hide the "Tools → Export All URLs" menu.
	remove_submenu_page('tools.php', 'extract-all-urls-settings');
}

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

Where do I put this code?