Those are harder to crack but can be done. Most password crackers for those are brute force/Dictionary attacks but I think there is one out there that strips the password from the file. Both are going to take a while to run how fast is your computer ?
I will have to look around and see if there are any free ones out there. I know there are a few that cost about $30 that can run the brute force/dictionary attacks but you might be able to find places to get them cheaper.
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