I plan to rebel against one rule, because: chainsaw.PullCord("RRRRAR!") looks much nicer to me than: chainsaw.pull_cord("RRRRAR!")
Well, that's up to you, as long as you're aware that it will be regarded as unusual and jarring by experienced Python users. The guidelines are there because it's a lot easier to write and read code if different libraries use a consistent naming style.
-- Greg