def METHOD_NAME(self):
    """
    Finish setting up the serial port.
    This is a separate method to facilitate testing.
    """
    flags, comstat = self._clearCommError()
    rc, self.read_buf = win32file.ReadFile(
        self._serial._port_handle,
        win32file.AllocateReadBuffer(1),
        self._overlappedRead,
    )