[Tutor] Humbly Announcing: cipher.py

[Tesla Coil]

I've put together a small module of functions frequently used
in a variety of pencil and paper cryptosystems--cipher.py is
appropriately available at Rob Andrews' Useless Python page:
http://www.lowerstandard.com/python/pythonsource.html

I'm interested in review of the existing functions and deciding
possible additions for a future release.

Persons with too much time on their hands are invited to give
a whack at using the module to write a Playfair cipher.  This
one turns up occasionally as a programming contest problem:
http://www.pbs.org/wgbh/nova/decoding/playfair.html

Currently wasting my own time to provide a demonstration of
a completely different keysquare cipher...