How to Hide the "WebSub/PubSubHubbub" Admin Menu

function plt_hide_pubsubhubbub_menus() {
	//Hide the "Settings → WebSub/PubSubHubbub" menu.
	remove_submenu_page('options-general.php', 'pubsubhubbub');
}

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

Where do I put this code?