collections.Counter surprisingly slow

[Roy Smith]

In article <51f5843f$0$29971$c3e8da3$5496439d at news.astraweb.com>,
 Steven D'Aprano <steve+comp.lang.python at pearwood.info> wrote:

> > Why is count() [i.e. collections.Counter] so slow?
> 
> It's within a factor of 2 of test, and 3 of exception or default (give or 
> take). I don't think that's surprisingly slow.

It is for a module which describes itself as "High-performance container 
datatypes" :-)