code: def start_processing_handler(self, event):
          
          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()
docs: Asynchronous handler starting the disk analysis process.