>>> class Cris(object):
...   favorites = ['python', 'zope', 'plone', 'django', 'pyramid']
...   def __lt__(self, other):
...     if other == 3:
...       import random
...       print random.choice(self.favorites)
...
>>> cris = Cris()
>>> cris <3
zope
>>> cris <3
django
>>> cris <3
python
>>>