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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 on(self):
 """Send the On command to an X10 device."""

        msg = X10Send.unit_code_msg(self.address.x10_housecode,
                                    self.address.x10_unitcode)
        self._send_method(msg)

        msg = X10Send.command_msg(self.address.x10_housecode,
                                  X10_COMMAND_ON)
        self._send_method(msg, False)
        self._update_subscribers(0xff)