Hi George, 

> From these results, it appears there is no guarentee that the signal handler will run before the main thread continues execution at the time.sleep(500) line.  This would explain why we advance to the else clause before the exception is raised.

To me it looks like the problem pops up *way* before the `sleep(100)` (or whatever) finishes, in fact it looks consistently like the sleep is indeed interrupted after one second.  I would it thus interpret differently, as the code should not be able to advance to the `else` clause at that time.

Is that different for you?