Python: Find objects of a certain type in memory

"""
    This looks through all the objects in memory, to find ones
    of the designated type.
"""
 
import gc
 
class Animal(object):
    def make_noise(self):
        print "snort"
 
animal = Animal()
 
for obj in gc.get_objects():
    if type(obj) == Animal:
        obj.make_noise()