def test_logPrefix(self):
        """
        L{TuntapPort.logPrefix} returns a string identifying the application
        protocol and the type of tunnel.
        """
        self.assertEqual(
            "%s (%s)" % (
                self.protocol.__class__.__name__,
                self._tunnelTypeOnly(self.helper.TUNNEL_TYPE).name),
            self.port.logPrefix())

        L{TuntapPort.logPrefix} returns a string identifying the application
        protocol and the type of tunnel.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/pair/test/test_tuntap.py