生成器的妙用

                利用yield来实现
                def test(request):
                    user_list = [
                        {'id':1,'name':'alex','age':19},
                        {'id':2,'name':'eric','age':18},
                    ]

                    def inner(arg):
                        for item in arg:
                            yield {'id':item['id'], 'name':item['name'],'age':item['id']+item['age']}


                    return render(request,'test.html',{'user_list':inner(user_list)})

                利用类、__iter__、yield实现
                
                class Foo(object):
                    def __init__(self,data):
                        self.data = data

                    def __iter__(self):
                        for item in self.data:
                            yield item

                def test(request):
                    user_list = [
                        {'id':1,'name':'alex','age':19},
                        {'id':2,'name':'eric','age':18},
                    ]
                    obj = Foo(user_list)
                    return render(request,'test.html',{'user_list':obj})