SPE is a Python IDE with auto indentation & completion, call tips, syntax coloring & highlighting, uml viewer, class explorer, source index, to do list, py crust shell, etc… I realize this may make it “too easy” for those purists who want to be able to code on the command line without help, but there it is. Very happy Windows tool. More: http://pythonide.stani.be/
Notepad++ also offers automatic indentation, intellisense (completing/suggesting coding terms before you finish typing them), coloring and other features. And it’s very easy to learn.
According to various online reviews Notepad++ always seems to rank as one of the most popular coding editors (not just for Python but other languages, too).