Can be done. The script uses os.path.walk, the callback function that is called can be modified to return immediately when a file is in a certain set of folders. Maybe it's easier to mark the folders (including content) you don't want to changed as read-only. The script will try to do the conversions, but it won't be able to. Since exception handling is in place, the script then will just skip those files and start handling the next files.

The pen is mightier than the sword. But if you literally want to have some impact, use a typewriter

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