[Zope] Style guide?

Having read the Python style guide (and having found it, if a bit confusing, at least not intolerably strict), I am now curious about what style people like to use in Zope. Are folders classes, or objects? In the examples in the Book, most of the folders are done in StudlyCaps, while the documents and methods are in mixedCase. Although, of course, index_html is under- score_separated. Aigh! Is there any consistent guide to this? I generally prefer good old underscores, having come from a Perl background. Looking on the web gives me the ZDP's style guide for their documentation, but not for Zope itself. Any guidance would be much appreciated. I hope I have not revived an old holy war. --JB