How to Hide VatanSMS.NET Admin Menus

function plt_hide_vatansms_net_menus() {
	//Hide "VatanSMS".
	remove_menu_page('vatansms');
	//Hide "VatanSMS → Giriş Yap".
	remove_submenu_page('vatansms', 'vatansms');
	//Hide "VatanSMS → Wordpress".
	remove_submenu_page('vatansms', 'vatansms-wordpress-sms');
	//Hide "VatanSMS → SMS Gönder".
	remove_submenu_page('vatansms', 'vatansms-sms-send');
	//Hide "VatanSMS → SMS Gönder (Toplu)".
	remove_submenu_page('vatansms', 'vatansms-sms-send-all');
	//Hide "VatanSMS → Woocommerce".
	remove_submenu_page('vatansms', 'vatansms-woocommerce');
	//Hide "VatanSMS → Contact Form 7".
	remove_submenu_page('vatansms', 'vatansms-contact-form-7');
	//Hide "VatanSMS → WP Form".
	remove_submenu_page('vatansms', 'vatansms-wp-form');
	//Hide "VatanSMS → SMS Raporları".
	remove_submenu_page('vatansms', 'vatansms-sms-reports');
}

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

Where do I put this code?