Message 252161 - Python tracker

I'm now closing this issue because Antoine, Serhiy and me dislike the idea.

> An alternate suggestion would be to allow filenames like "Lib/test/test_foo.py" as arguments to regrtest.

This sounds like a better plan. Please open a new issue if you still need that.

FYI I refactoring regrtest.py into libregrtest, it might be easier to enhance it now.