从列表中删除重复的项目

Question

我尝试过这篇文章但是,它似乎并不适合我.

我试过这段代码:

for bresult in response.css(LIST_SELECTOR):
    NAME_SELECTOR = 'h2 a ::attr(href)'
    yield {
        'name': bresult.css(NAME_SELECTOR).extract_first(),
    }
                                                                                  b_result_list.append(bresult.css(NAME_SELECTOR).extract_first())

    #set b_result_list to SET to remove dups, then change back to LIST
    set(b_result_list)
    list(set(b_result_list))
for brl in b_result_list:
    print("brl: {}".format(brl))

打印出:

brl: https://facebook.site.com/users/login
brl: https://facebook.site.com/users
brl: https://facebook.site.com/users/login

当我需要时:

brl: https://facebook.site.com/users/login
brl: https://facebook.site.com/users

我在这做错了什么？

谢谢!

Answer 1

你需要保存它时丢弃结果... b_result_list从不实际更改...所以你只是迭代原始列表.而是保存set操作的结果

b_result_list = list(set(b_result_list))

(注意sets不保留顺序)