How to Hide Rich Coming Soon - Maintenance Mode & Under Construction Admin Menus

function plt_hide_coming_soons_menus() {
	//Hide the "Coming Soon" menu.
	remove_menu_page('Rich-Web CS Admin');
	//Hide the "Coming Soon → Coming Soon" menu.
	remove_submenu_page('Rich-Web CS Admin', 'Rich-Web CS Admin');
	//Hide the "Coming Soon → Our Products" menu.
	remove_submenu_page('Rich-Web CS Admin', 'Rich-Web Coming Soon Products');
}

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

Where do I put this code?