カウンタ

def counts():
    def f(): #          
        x = 0
        while True:
            x = x + 1
            yield x

    it = f()
    def number():
        num = next(it)
        return num

    return number

counts_demo = counts()
while True:
    num = counts_demo()
    print(num)
    if num > 10:
        break