How to Hide WebinarPress Admin Menus

function plt_hide_wp_webinarsystem_menus() {
	//Hide "WebinarPress".
	remove_menu_page('wswbn-webinars');
	//Hide "WebinarPress → Webinars".
	remove_submenu_page('wswbn-webinars', 'wswbn-webinars');
	//Hide "WebinarPress → New Webinar".
	remove_submenu_page('wswbn-webinars', 'wswbn-webinar-editor');
	//Hide "WebinarPress → Attendees".
	remove_submenu_page('wswbn-webinars', 'wswbn-attendees');
	//Hide "WebinarPress → Questions".
	remove_submenu_page('wswbn-webinars', 'wswbn-questions');
	//Hide "WebinarPress → Settings".
	remove_submenu_page('wswbn-webinars', 'wswbn-settings');
	//Hide "WebinarPress → Upgrade to PRO".
	remove_submenu_page('wswbn-webinars', 'wswbn-upgrade');
}

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

Where do I put this code?