I prefer emacs for all my development and python is no exception. With a little bit of tweaking one can turn emacs into a powerful python IDE complete with syntax highlighting, auto completion, and more. Couple that with a split screen running a python shell and I cant imagine being any more productive. That is, unless you are an avid vim user ;)
Here are a few good tutorials to get you set up and running.
#you'll need to read the comments for some necessary corrections on this guide, specifically changing some of his backticks to commas in the lisp code.
hope this helps.