Python 2.7.3 (default, Jun 18 2012, 17:45:15)
[GCC 4.5.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> import collections
>>> point = collections.namedtuple('Point',['x','y'])
>>> class PointClass(object):
...     __slots__=['x','y']
...
>>> sys.getsizeof(point)
904
>>> sys.getsizeof(PointClass)
904
>>> inst1 = point(x=1,y=2)
>>> inst2 = PointClass()
>>> inst2.x = 1
>>> inst2.y = 2
>>> sys.getsizeof(inst1)
72
>>> sys.getsizeof(inst2)
64