image color gets changed in python code example

Example: find all color in image python

>>> from PIL import Image
>>> im = Image.open('polar-bear-cub.jpg')
>>> from collections import defaultdict
>>> by_color = defaultdict(int)
>>> for pixel in im.getdata():
...     by_color[pixel] += 1
>>> by_color
defaultdict(<type 'int'>, {(11, 24, 41): 8, (53, 52, 58): 8, (142, 147, 117): 1, (121, 111, 119): 1, (234, 228, 216): 4