def test_unix(self):
        """
        When passed a UNIX strports description, L{endpoint.serverFromString}
        returns a L{UNIXServerEndpoint} instance initialized with the values
        from the string.
        """
        reactor = object()
        endpoint = endpoints.serverFromString(
            reactor,
            "unix:/var/foo/bar:backlog=7:mode=0123:lockfile=1")
        self.assertIsInstance(endpoint, endpoints.UNIXServerEndpoint)
        self.assertIs(endpoint._reactor, reactor)
        self.assertEqual(endpoint._address, "/var/foo/bar")
        self.assertEqual(endpoint._backlog, 7)
        self.assertEqual(endpoint._mode, 0o123)
        self.assertTrue(endpoint._wantPID)

        When passed a UNIX strports description, L{endpoint.serverFromString}
        returns a L{UNIXServerEndpoint} instance initialized with the values
        from the string.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_endpoints.py