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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 id(self):
 """Return the ID of the device address."""

        dev_id = ''
        if self._is_x10:
            dev_id = 'x10{}{:02d}'.format(self.x10_housecode,
                                          self.x10_unitcode)
        else:
            dev_id = self.hex
        return dev_id