stop script w/o exiting interpreter

[Alan Isaac]

I'm fairly new to Python and I've lately been running a script at
the interpreter while working on it.  Sometimes I only want to
run the first quarter or half etc.  What is the "good" way to do this?

Possible ugly hacks include:

- stick an undefined name at the desired stop point
- comment out the last half

I do not like these and assume that I have overlooked the obvious.

Thanks,
Alan Isaac