Tweaked patch to apply cleanly to trunk, but realised it has been a while since I looked at the current state of argument clinic:

* I'm not sure if varargs support has been added yet. If it has, "min", "max", "print", "__build_class__" can be converted. If it hasn't, then the comments referring to 3.4 still need to be updated.

* the comments referring to needing groups support in AC aren't quite right, it's optional group support in inspect that's missing. So the comments relating to "range", "slice", "dir", "getattr", "next", "iter", "vars" should be tweaked accordingly

* tweaking the behaviour of round to make it AC friendly should probably go into its own issue.

Also, Larry, there's a note in the the 3.4 "What's New" about additional signature info landing in Python 3.4 maintenance releases. That note should probably be adjusted at this point, since any new signature data will only be available in 3.5.