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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 start_processing_handler(self, event):
 """Asynchronous handler starting the disk analysis process."""

        results_path = os.path.join(self.configuration['results_folder'],
                                    "filesystem.json")
        self.logger.debug("Event %s: start comparing %s with %s.",
                          event, self.checkpoints[0], self.checkpoints[1])

        results = compare_disks(self.checkpoints[0], self.checkpoints[1],
                                self.configuration)

        with open(results_path, 'w') as results_file:
            json.dump(results, results_file)

        self.processing_done.set()