[mgreenbe]

Settling on language-wide naming conventions reduces cognitive dissonance. Naming conventions don't supplant reading library docs, but they support it. In any case, you have to pick something, and some people will always be dissatisfied.

The answer to any "who says" question about Python is "Guido van Rossum says". (In the case of PEP 8, Barry Warsaw says as well.)

[yesimahuman]

I agree, but I don't agree that deviating from PEP 8 in terms of naming makes one a bad python programmer. I've seen so many deviations of these rules in libraries that if I were to expect a certain style I would be more frustrated than I am.