def test_badExchangeExcluded(self):
        domain = "example.com"
        good = "good.example.com"
        bad = "bad.example.com"

        records = [
            RRHeader(name=domain,
                     type=Record_MX.TYPE,
                     payload=Record_MX(0, bad)),
            RRHeader(name=domain,
                     type=Record_MX.TYPE,
                     payload=Record_MX(1, good))]
        self.mx.markBad(bad)
        return self._exchangeTest(domain, records, good)
L{MXCalculator.getMX} returns the MX record with the lowest preference
dataset/ETHPy150Open kuri65536/python-for-android/python-modules/twisted/twisted/mail/test/test_mail.py/MXTestCase.test_badExchangeExcluded