Already quite a few solutions here, but yet another way of doing that would be -
anims = []images = [f for f in files if (lambda t: True if f[2].lower() in IMAGE_TYPES else anims.append(t) and False)(f)]Iterates over the list only once, and looks a bit more pythonic and hence readable to me.
>>> files = [ ('file1.jpg', 33L, '.jpg'), ('file2.avi', 999L, '.avi'), ('file1.bmp', 33L, '.bmp')]>>> IMAGE_TYPES = ('.jpg','.jpeg','.gif','.bmp','.png')>>> anims = []>>> images = [f for f in files if (lambda t: True if f[2].lower() in IMAGE_TYPES else anims.append(t) and False)(f)]>>> print '\n'.join([str(anims), str(images)])[('file2.avi', 999L, '.avi')][('file1.jpg', 33L, '.jpg'), ('file1.bmp', 33L, '.bmp')]>>>