Python 自己实现可迭代对象

import time
from collections import Iterable
from collections import Iterator

class Classmate(object):
    def __init__(self):
        self.names = list()
        self.current_num = 0

    def add(self, name):
        self.names.append(name)

    def __iter__(self):
        """ 如果想要一个对象称为一个可迭代的对象，即可以使用for，那么必须得实现__iter__方法 """
        return self

    def __next__(self):
        if self.current_num < len(self.names):
            ret = self.names[self.current_num]
            self.current_num += 1
            return ret
        else:
            raise StopIteration

classmate = Classmate()
classmate.add("张三")
classmate.add("李四")
classmate.add("王五")
print("判断classmate是否是可以迭代的对象:", isinstance(classmate, Iterable))
print("判断classmate是否是迭代器:", isinstance(classmate, Iterator))
for name in classmate:
    print(name)
    time.sleep(1)