I disagree on this being "magical", I tend to think of it as "Pythonic". If there is a reasonably easy to remember construct (such as this one: if you've seen it once you'll remember it) just use that, in stead of adding extra layers of functionality.
to quote a certain bot (guess raymond wasn't following that thread):
"It's easier to write appropriate code from scratch in Python than to figure out how to *use* a package profligate enough to contain canned solutions for all common and reasonable use cases."
time to add a best_practices module to Python 2.3?
KeyError:-profligate-ly yrs /F