python迭代器

class Fibs:
    def __init__(self):
        self.a = 0
        self.b = 1
    def __next__(self):   #def next(self):   如果写成这样会报错 TypeError: iter() returned non-iterator of type ‘Fibs‘

        self.a, self.b = self.b, self.a + self.b
        return self.a
    def __iter__(self):
        return self
fibs = Fibs()
for f in fibs:
    if f > 1000:
        print(f)
        break