Utils.cycle(values)

Creates a function that returns the next value of an array every time it's called.
译：创建一个函数，它每次调用时返回一个数组的下一个值。

Arguments（参数）

values — An array of values. 译：数组的值。

cycler = Utils.cycle(["a", "b", "c"])

print cycler() # Output: "a" 
print cycler() # Output: "b" 
print cycler() # Output: "c" 
print cycler() # Output: "a", returns to start