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http://manage.dimagi.com/default.asp?130862#777250

http://manage.dimagi.com/default.asp?141280
i'm not @dannyroberts but i think it makes sense. if you changed the slug then the existing toggles would all break so we should treat that as immutable. it makes sense to me to use python `ALL_CAPS` things when you have access to them in python, but rely on the slugs outside of that.