> Just to me it clear - why do you want warn() to be removed aside from code 

> duplication?
> 
> My argument to leave it and document is that it is convenient and makes lines 
> shorter (and won't break existing code). From logging module I also see that 
> there are also logging.WARN aliases that you'll need to deprecate also.

Sorry, I don't agree. I was happy to leave it as is until you raised this issue, but now I think the right thing to do is deprecate and remove warn(). I'm not too fussed about the WARN level, and I can't easily issue a deprecation warning for it as it's a module attribute, so I'll leave it in as an internal implementation detail, for which the usual caveats apply.