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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 background_scan(content_dir):
 """ Start background scanning a directory for changes """

    observer = watchdog.observers.Observer()
    observer.schedule(IndexWatchdog(content_dir),
                      content_dir, recursive=True)
    logging.info("Watching %s for changes", content_dir)
    observer.start()