def test_serialPortDefaultArgs(self):
        """
        Test correct positional and keyword arguments have been
        passed to the C{serial.Serial} object.
        """
        port = RegularFileSerialPort(self.protocol, self.path, self.reactor)
        # Validate args
        self.assertEqual((self.path,), port._serial.captured_args)
        # Validate kwargs
        kwargs = port._serial.captured_kwargs
        self.assertEqual(9600,                kwargs["baudrate"])
        self.assertEqual(serial.EIGHTBITS,    kwargs["bytesize"])
        self.assertEqual(serial.PARITY_NONE,  kwargs["parity"])
        self.assertEqual(serial.STOPBITS_ONE, kwargs["stopbits"])
        self.assertEqual(0,                   kwargs["xonxoff"])
        self.assertEqual(0,                   kwargs["rtscts"])
        self.assertEqual(None,                kwargs["timeout"])
        port.connectionLost(Failure(Exception("Cleanup")))

        Test correct positional and keyword arguments have been
        passed to the C{serial.Serial} object.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/internet/test/test_win32serialport.py