python:生成器

#斐波那契数列，1，1，2，3，5，8，13，21，34，55
def fib(max):

    n,a,b =0,0,1
    while n < max:
        print(b)
        a,b=b,a+b
        n=n+1
    # return "done"
fib(10)

code=‘‘‘def fib(max):
    n,a,b =0,0,1
    while n < max:
        yield b
        a,b=b,a+b
        n=n+1
    return ‘----done-----------‘
f=fib(5)
while True:
    try:
        x=next(f)
        print("f:",x)
    except StopIteration as e:
        print("Generator return value:",e.value)
        break
‘‘‘
exec(code)