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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 list_devices(self):
 """List devices in the ALDB."""

        if self.plm.devices:
            for addr in self.plm.devices:
                device = self.plm.devices[addr]
                if device.address.is_x10:
                    _LOGGING.info('Device: %s %s', device.address.human,
                                  device.description)
                else:
                    _LOGGING.info('Device: %s cat: 0x%02x subcat: 0x%02x '
                                  'desc: %s, model: %s',
                                  device.address.human, device.cat,
                                  device.subcat, device.description,
                                  device.model)
        else:
            _LOGGING.info('No devices found')
            if not self.plm.transport:
                _LOGGING.info('IM connection has not been made.')
                _LOGGING.info('Use `connect [device]` to open the connection')