What's the best editor/IDE for Python?
It’s really a matter of preference. There are many features of an editor or IDE such as syntax highlighting, code completion, code folding, buffers, tabs, support for multiple platforms, and so on. Each editor or IDE has some or all of these features, and you’ll have to decide which features are important to you.
See http://wiki.python.org/moin/PythonEditors for a list of editors, and http://wiki.python.org/moin/IntegratedDevelopmentEnvironments for a list of IDEs.
This question is asked every few weeks on comp.lang.python so searching the archives will yield many opinions.