### Question:
CountryUtils { static boolean doesCountryUsePostalCode(@NonNull String countryCode) { return !NO_POSTAL_CODE_COUNTRIES_SET.contains(countryCode); }    }### Answer:
@Test public void postalCodeCountryTest() { assertTrue(CountryUtils.doesCountryUsePostalCode("US")); assertTrue(CountryUtils.doesCountryUsePostalCode("UK")); assertTrue(CountryUtils.doesCountryUsePostalCode("CA")); assertFalse(CountryUtils.doesCountryUsePostalCode("DM")); }