2.2 features

[Guido van Rossum]

> I'm starting to like the is{subclass,instance}() version. It's probably
> quicker for one to understand code written by others, and for
> non-fulltime-python-programmers to remember what "in" means in each
> context.

You may be right.  isinstance() and issubclass() are somewhat standard
in other languages I believe, and hard to misunderstand.  The form

  if x in list: ...

looks a lot more confusing.  I may withdraw this idea.

--Guido van Rossum (home page: http://www.python.org/~guido/)