python之获取空白列表之不知道为什么

我使用这段代码:

from __future__ import division 
from __future__ import print_function 
 
in_file = open("s:/Personal Folders/Andy/Python Projects/People Cancelled/Analyze Authorize Truncated.csv") 
text = in_file.readlines() 
in_file.close() 
 
header = text[0:1] 
text = text[1:] 
 
for index, line in enumerate(text): 
    text[index] = line.split(",") 
 
name = text 
dates = text 
 
for index, line in enumerate(name): 
    name[index] = line[3:5] 
 
for stuff, area in enumerate(dates): 
     dates[stuff] = area[7:8] 
 
print(name) 
print(dates) 

我得到了这个输出:

 [[], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], []] 
 [[], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], [], []] 

知道为什么吗？出于某种原因，两个 for 循环之间似乎存在某种干扰 - 如果我单独执行其中一个，我会得到我想要的结果。

谢谢!

请您参考如下方法:

看这两行:

name = text 
date = text 

这些行不复制要指向的名称和日期的文本；相反，他们将名称和日期设置为实质上文本的替代名称。因此，在第三个 for 循环之后(主体 name[index] = line[3:5]，text 中的每一行都是两个项目长(因为 text 和 name 是同一个列表。事实上，我什至不明白为什么要将 name 和 date 设置为相等最初为 text；通过使 name 和 date 等于新的空列表并根据文本。