python 迭代器

迭代器使用方法：

#!/usr/bin/env python
# !-*-coding:utf-8-*-
__author__ = 't'

class anyIter(object):
    def __init__(self, li):
        self.li =iter(li)

    def __iter__(self):
        return self

    #重写了 iter 中的next方法.
    def next(self, howmany=1):
        retval = None
        for eachItem in range(howmany):
            try:
                retval = self.li.next()
            except Exception, e:
                break
        return retval

li = [1, 3, 4, 5, 6, 7, 8, 9]
a = anyIter(li)
i = iter(a)
for s in range(13):
    print i.next()