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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):
 """Periodic cleanup tasks to maintain this adapter, should be called every second """


        if self.stopped:
            return

        # Check if we should start scanning again
        if not self.scanning and len(self._connections) == 0 and self.connecting_count == 0:
            self._logger.info("Restarting scan for devices")
            self.start_scan(self._active_scan)
            self._logger.info("Finished restarting scan for devices")