def test_requestExec(self):
        """
        When a client requests a command, the SSHSession object should get
        the command by getting an ISession adapter for the avatar, then
        calling execCommand with a ProcessProtocol to attach and the
        command line.
        """
        ret = self.session.requestReceived(b'exec',
                                           common.NS(b'failure'))
        self.assertFalse(ret)
        self.assertRequestRaisedRuntimeError()
        self.assertIsNone(self.session.client)

        self.assertTrue(self.session.requestReceived(b'exec',
                                                     common.NS(b'success')))
        self.assertSessionIsStubSession()
        self.assertIsInstance(self.session.client,
                              session.SSHSessionProcessProtocol)
        self.assertIs(self.session.session.execProtocol, self.session.client)
        self.assertEqual(self.session.session.execCommandLine,
                b'success')

        When a client requests a command, the SSHSession object should get
        the command by getting an ISession adapter for the avatar, then
        calling execCommand with a ProcessProtocol to attach and the
        command line.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_session.py