[1] in C++ I would call that a "mixin"
Mixins are perfectly valid Python constructs as well and are perfectly valid (imho) for this use case.
On a side note, I usually append a "Mixin" suffix to my mixin classes in order to make it obvious to the reader.
-- Demian Brecht @demianbrecht http://demianbrecht.github.com -- http://mail.python.org/mailman/listinfo/python-list
