用途itertools.cycle()：

from itertools import cycle
myIterator = cycle(range(2))

myIterator.next()   # or next(myIterator) which works in Python 3.x. Yields 0
myIterator.next()   # or next(myIterator) which works in Python 3.x. Yields 1
# etc.

请注意，如果您需要比更为复杂的周期[0, 1]，那么此解决方案将比此处发布的其他解决方案更具吸引力。

from itertools import cycle
mySmallSquareIterator = cycle(i*i for i in range(10))
# Will yield 0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 0, 1, 4, ...