Really?  The re module cannot be salvaged and we should add regex but keep the (buggy) re?  That does not make a lot of sense to me.  I think it should just be fixed in the re module.  Or the re module should be *replaced* by the code from the regex module (but renamed to re, and with certain backwards compatibilities restored, probably).  But I really hope the re module (really: the _sre extension module) can be fixed.  We should also make a habit in our docs of citing specific versions of the Unicode standard, and specific TR numbers and versions where they apply.  (And hopefully we can supply URLs to the Unicode consortium's canonical copies of those documents.)