formatToMany example

array $countries = null,
        array $overwrites = []
    ): string {
        $context = Context::createDefaultContext();

        $languageId ??= Defaults::LANGUAGE_SYSTEM;
        $currencyId ??= Defaults::CURRENCY;
        $paymentMethodId ??= $this->getFirstActivePaymentMethodId();
        $shippingMethodId ??= $this->getFirstActiveShippingMethodId();
        $countryId ??= $this->getFirstActiveCountryId();

        $currencies = $this->formatToMany($currencies, $currencyId, 'currency', $context);
        $languages = $this->formatToMany($languages, $languageId, 'language', $context);
        $shippingMethods = $this->formatToMany($shippingMethods, $shippingMethodId, 'shipping_method', $context);
        $paymentMethods = $this->formatToMany($paymentMethods, $paymentMethodId, 'payment_method', $context);
        $countries = $this->formatToMany($countries, $countryId, 'country', $context);

        $data = [
            'id' => $id,
            'name' => $name,
            'typeId' => $typeId,
            'accessKey' => AccessKeyHelper::generateAccessKey('sales-channel'),