def test_nonNumericTTLRaisesTypeError(self):
        """
        Attempting to create a L{dns.RRHeader} instance with a TTL
        that L{int} cannot convert to an integer raises a L{TypeError}.
        """
        self.assertRaises(
            ValueError, dns.RRHeader, "example.com", dns.A,
            dns.IN, "this is not a number", dns.Record_A("127.0.0.1"))

        Attempting to create a L{dns.RRHeader} instance with a TTL
        that L{int} cannot convert to an integer raises a L{TypeError}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_dns.py