类中__iter__与__next__的说明

class Fab(object):
    def __init__(self ,max ):
        self.max =max
        self.n =0
        self.a=0
        self.b =1
    def __iter__(self):    #迭代器，表示为容器，相当于声明
        return self
    def __next__(self):    #迭代内容
        print('n=',self.n)
        self.n=1+self.n
        if self.n < self.max:
            out = self.b
            return out
        # raise StopIteration()
c=0
for i in Fab(13):
    c=1+c
    print(i)
    print('c=',c)
    if c>20:
        # a = Fab(3)
        # print(a)
        break