Python has a builtin tool to do rot13 (among other things)

Look in the codecs module.

I was reminded of this while looking at some old tweets; the codecs module knows how to do rot13, hex, or even zip files:

>>> import codecs
>>> codecs.encode('abc', encoding='rot13')
'nop'
>>> codecs.encode(b'abc', encoding='hex')
b'616263'
>>> codecs.encode(b'abc', encoding='zip')
b"x\x9cKLJ\x06\x00\x02M\x01'"

I don’t know that I have a practical use for this right now, but it’s kinda neat.