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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 refresh(self):
 """ Refreshes the internal lookup table if necessary. """

        try:
            self._private_to_public = self.cloud_discovery.discover_nodes()
        except Exception as ex:
            self.logger.warning("Failed to load addresses from Hazelcast.cloud: {}".format(ex.args[0]),
                                extra=self._logger_extras)