Benjamin Dauvergne  wrote:
> This module has been deprecated in python 2.6, it should be ok to
> replace it by a frozenset instance.

Version 2.7 will use the built-in set instead. The idea is that 2.7
will drop support for older versions of Python and will make it
easier to transition to Python 3.  This is in the git repository on
quixote.ca.

Cheers,

  Neil