You're asking for the encryption key to be derivable by an unrelated system that only has the encrypted file and your password.
Yes, that's kind of what you need to be able to successfully back up and restore an encrypted file. Why are you making it sound like that's such a strange thing to want?
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Yes, that's kind of what you need to be able to successfully back up and restore an encrypted file. Why are you making it sound like that's such a strange thing to want?