def test_init(self):
        """
        SSHSession initializes its buffer (buf), client, and ISession adapter.
        The avatar should not need to be adaptable to an ISession immediately.
        """
        s = session.SSHSession(avatar=object) # use object because it doesn't
                                              # have an adapter
        self.assertEqual(s.buf, b'')
        self.assertIsNone(s.client)
        self.assertIsNone(s.session)

        SSHSession initializes its buffer (buf), client, and ISession adapter.
        The avatar should not need to be adaptable to an ISession immediately.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_session.py