枚举元组列表时,我得到TypeError:'type'对象没有属性'__getitem__'

时间:2016-02-09 17:50:38

标签: python csv tuples typeerror

下面的脚本读取CSV文件并创建名为people的元组列表。元组是patron_id(唯一字符串标识符)和person信息字典。

对于数据样本(简化了名称信息已移除),如下所示:

patron_id    show_id
1111MAIN       MW1
2222SCOTT      MW2
1111MAIN       MW1

脚本应该输出一个元组列表,如下所示:

[ ("1111MAIN", {'patron_id': "1111MAIN", 'show_list': ["MW1", "MW2"]}), ("2222SCOTT", {'patron_id': "2222SCOTT", 'show_list': ["MW2"]}) ]

该脚本在回溯中引发以下错误:

File "frequency.py", line 75, in <module> main("input.csv") File "frequency.py", line 35, in main person_index = [x for x, y in enumerate[people] if y[0] == patron_id]

当我在shell中手动测试这一行时,它返回我正在搜索的元组的索引。为什么这行在脚本中失败了?

import csv

def main(filename):
    people = [] #list of person tuples
    person = {} #patron info with list of unique shows

    #open csv data
    csv_file = csv.reader(open(filename, 'rb'))

    #read and define CSV data
    for record in csv_file:
        show_list = []

        patron_id = record[0]
        first_name = record[1]
        last_name = record[2]
        show_name = record[3]

        #check if this is the first row
        if len(people) == 0:
            show_list.append(show_name)
            person = (patron_id, {'patron_id': patron_id, 'first_name': first_name, 'last_name': last_name, 'show_list': show_list})
            people.append(person)

        else:

            #if this person IS in the list of people
            if any(patron_id in person for person in people) == True:
                #retrieve this person from people by finding its index          
                person_index = [x for x, y in enumerate[people] if y[0] == patron_id][0]

2 个答案:

答案 0 :(得分:3)

您需要将enumerate[people]更改为enumerate(people)。当您使用括号时,python认为您尝试访问enumerate位置的people。相反,你需要调用它。

答案 1 :(得分:3)

好吧,正如我的评论中所述,问题是您尝试使用方括号调用__getitem__ enumerate方法,因为它没有此方法,因此必然会失败。要构造枚举对象,请使用括号。

尝试密切关注错误消息,通常它们很有帮助。我不需要阅读您的整个代码来查找错误。