def test_resolverUsesOnlyParameterizedReactor(self):
        """
        If a reactor instance is supplied to L{client.Resolver}
        L{client.Resolver._connectedProtocol} should pass that reactor
        to L{twisted.names.dns.DNSDatagramProtocol}.
        """
        reactor = test_util.MemoryReactor()
        resolver = client.Resolver(resolv=self.mktemp(), reactor=reactor)
        proto = resolver._connectedProtocol()
        self.assertIs(proto._reactor, reactor)

        If a reactor instance is supplied to L{client.Resolver}
        L{client.Resolver._connectedProtocol} should pass that reactor
        to L{twisted.names.dns.DNSDatagramProtocol}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_client.py