How to Hide ELEX WordPress Live Chat (WSChat) Admin Menus

function plt_hide_wschat_live_chat_menus() {
	//Hide "WSChat".
	remove_menu_page('wschat_chat');
	//Hide "WSChat → Live Chat".
	remove_submenu_page('wschat_chat', 'wschat_chat');
	//Hide "WSChat → Tags".
	remove_submenu_page('wschat_chat', 'wschat_tags');
	//Hide "WSChat → Chat History".
	remove_submenu_page('wschat_chat', 'wschat_history');
	//Hide "WSChat → Live Visitors [Premium]".
	remove_submenu_page('wschat_chat', 'wschat_live_visitors');
	//Hide "WSChat → Agents".
	remove_submenu_page('wschat_chat', 'wschat_agents');
	//Hide "WSChat → Settings".
	remove_submenu_page('wschat_chat', 'wschat_settings');
	//Hide "WSChat → Help & Support".
	remove_submenu_page('wschat_chat', 'wschat_helpandsupport');
	//Hide "WSChat → Go Premium!".
	remove_submenu_page('wschat_chat', 'wschat_gopremium');
}

add_action('admin_menu', 'plt_hide_wschat_live_chat_menus', 11);
Where do I put this code?