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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def open(self):
 """ Open the HID device for reading and writing. """

        if self._is_open:
            raise HIDException("Failed to open device: HIDDevice already open")

        path = self.path.encode('utf-8')
        dev = hidapi.hid_open_path(path)

        if dev:
            self._is_open = True
            self._device = dev
        else:
            raise HIDException("Failed to open device")