Possible Duplicates:
A good open source Python project to read code?
How to learn Python: Good Example Code?
I've been reading through Coders at Work and there is a repeated theme: hackers tend to read a lot of other's code and learn from it. I program in Python, there are plenty of open source code in it.
Which codebase you read and consider excellent? SQLAlchemy comes to mind. What else?
The standard library is good. Also when I created the compatibility tests in the Python-incompatibility code, I learnt a lot, so read that too.
The python standard library, as others have mentioned, is mostly good, but not really consistent. People should really be giving a module-by-module recommendation. Having read a few modules, I can tell you that many don't conform to what is considered good Python style (though they may perform well).
Probably the best code I have seen, just in terms of style, is Google App Engine's Python Library, which is browsable here.