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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 read_aldb(self, mem_addr=0x0000, num_recs=0):
 """Read the device All-Link Database."""

        if self._aldb.version == ALDBVersion.Null:
            _LOGGER.info('Device %s does not contain an All-Link Database',
                         self._address.human)
        else:
            _LOGGER.info('Reading All-Link Database for device %s',
                         self._address.human)
            asyncio.ensure_future(self._aldb.load(mem_addr, num_recs),
                                  loop=self._plm.loop)
            self._aldb.add_loaded_callback(self._aldb_loaded_callback)