Why not? Classes are fine for that.
If you want to save some memory, you might also want to use __slots__ so the objects don’t have a __dict__. See http://docs.python.org/reference/datamodel.html#slots for details and Usage of __slots__? for some useful information.
For example, a class holding only two values (a and b) could looks like this:
class AB(object):
__slots__ = ('a', 'b')
If you actually want a dict but with obj.item access instead of obj['item'], you could subclass dict and implement __getattr__ and __setattr__ to behave like __getitem__ and __setitem__.