def test_getHost(self):
        """
        L{IListeningPort.getHost} returns an L{IPv4Address} giving a
        dotted-quad of the IPv4 address the port is listening on as well as
        the port number.
        """
        host, portNumber = findFreePort(type=socket.SOCK_DGRAM)
        reactor = self.buildReactor()
        port = self.getListeningPort(
            reactor, DatagramProtocol(), port=portNumber, interface=host)
        self.assertEqual(
            port.getHost(), IPv4Address('UDP', host, portNumber))

        L{IListeningPort.getHost} returns an L{IPv4Address} giving a
        dotted-quad of the IPv4 address the port is listening on as well as
        the port number.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_udp.py