public function getCurrencyForCountry(string $countryCode) : Currency
    {
        $currencies = $this->getCurrenciesForCountry($countryCode);

        $count = count($currencies);

        if ($count === 1) {
            return $currencies[0];
        }

        if ($count === 0) {
            throw UnknownCurrencyException::noCurrencyForCountry($countryCode);
        }

        $currencyCodes = [];

        foreach ($currencies as $currency) {
            $currencyCodes[] = $currency->getCurrencyCode();
        }

        throw UnknownCurrencyException::noSingleCurrencyForCountry($countryCode, $currencyCodes);
    }