How to Hide WassUp Real Time Analytics Admin Menus

function plt_hide_wassup_menus() {
	//Hide "Dashboard → WassUp Stats".
	remove_submenu_page('index.php', 'wassup-stats');

	//Hide "WassUp".
	remove_menu_page('wassup');
	//Hide "WassUp → Visitor Details".
	remove_submenu_page('wassup', 'wassup');
	//Hide "WassUp → SPY Visitors".
	remove_submenu_page('wassup', 'wassup-spia');
	//Hide "WassUp → Current Visitors Online".
	remove_submenu_page('wassup', 'wassup-online');
	//Hide "WassUp → Options".
	remove_submenu_page('wassup', 'wassup-options');
}

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

Where do I put this code?