Message 63277 - Python tracker

Right now Python misses a wrapper for setitimer and getitimer and I
believe it would be interesting to include them. I'm (almost) sure some
other people may find it useful too.

I'm attaching a standalone module, but if it gets to be included in
Python, I think it would be better to create a patch against signal
module. Also, its tests are pretty poor. 

Improvements are welcomed.