def test_esmtpClientTlsModeDeprecationGetAttributeError(self):
        """
        L{smtp.ESMTPClient.__getattr__} raises an attribute error for other
        attribute names which do not exist.
        """
        self.assertRaises(
            AttributeError, lambda: self.clientProtocol.doesNotExist)

        L{smtp.ESMTPClient.__getattr__} raises an attribute error for other
        attribute names which do not exist.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/mail/test/test_smtp.py