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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 _save_pickle(self, filename):
 """Save sensors to pickle file."""

        with open(filename, 'wb') as file_handle:
            pickle.dump(self._sensors, file_handle, pickle.HIGHEST_PROTOCOL)
            file_handle.flush()
            os.fsync(file_handle.fileno())