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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 link_to_storage(self, sensor_log):
 """Attach this DataStreamer to an underlying SensorLog. Calling this method is required if you want to use this DataStreamer to generate reports from the underlying data in the SensorLog. You can call it multiple times and it will unlink itself from any previous SensorLog each time. Args: sensor_log (SensorLog):
 Actually create a StreamWalker to go along with this streamer so that we can check if it's triggered. """


        if self.walker is not None:
            self._sensor_log.destroy_walker(self.walker)
            self.walker = None

        self.walker = sensor_log.create_walker(self.selector)
        self._sensor_log = sensor_log