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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 add_x10_device(self, housecode, unitcode, dev_type):
 """Add an X10 device to the PLM."""

        device = None
        try:
            device = self.plm.devices.add_x10_device(self.plm, housecode,
                                                     unitcode, dev_type)
        except ValueError:
            pass
        return device