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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 periodic_callback(self):
 """Periodically help maintain adapter internal state """


        while True:
            try:
                action = self._deferred.get(False)
                action()
            except queue.Empty:
                break
            except Exception:
                self._logger.exception('Exception in periodic callback')