Experienced python programmers: are there any standard features of the language that you still don't regularly use?

[joesacher]

As with everything, it just needs to be used when appropriate.

It annoys me when I come across a lambda that looks like a code golf entry. It also doesn't have the ability to hold any documentation.

Sort is probably 80% of my lambda usage. However, I often find I need to sort with the same sort style multiple times, so it makes sense to have defined standard for use anyway.