def test_connectingCancelledError(self):
        """
        L{error.ConnectingCancelledError} has an C{address} attribute.
        """
        address = object()
        e = error.ConnectingCancelledError(address)
        self.assertIs(e.address, address)

        L{error.ConnectingCancelledError} has an C{address} attribute.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_error.py