private static function createSmartShoppingAd(
        AdWordsServices $adWordsServices,
        AdWordsSession $session,
        $adGroupId
    ) {
        $adGroupAdService =
            $adWordsServices->get($session, AdGroupAdService::class);

        // Create a Smart Shopping ad (Goal-optimized Shopping ad).
        $smartShoppingAd = new GoalOptimizedShoppingAd();

        // Create an ad group ad.
        $adGroupAd = new AdGroupAd();
        $adGroupAd->setAdGroupId($adGroupId);
        $adGroupAd->setAd($smartShoppingAd);

        // Create an ad group ad operation and add it to the operations list.
        $operation = new AdGroupAdOperation();
        $operation->setOperand($adGroupAd);
        $operation->setOperator(Operator::ADD);

        // Create the ad group ad on the server and print out some information.
        $addedAdGroupAd = $adGroupAdService->mutate([$operation])
            ->getValue()[0];
        printf(
            "Smart Shopping ad with ID %d was added.%s",
            $addedAdGroupAd->getAd()->getId(),
            PHP_EOL
        );
    }