访问嵌套列表 python 中的元组元素

Question

I'm new to python, I have a list with a nested list and inside it contains tuples it looks like below

[('dad', 'mom', 'test1.txt')]
[('brother', 'sister', 'test2.txt')]
[('uncle', 'aunty', 'test3.txt')]
[('grandpa', 'grandma', 'test4.txt')]

I would like to access one list at a time, for example, I open test1.txt file from 1st list index[2] and if the string 'dad' and 'mom' are present then filter the file and read it likewise for text2.txt file if 'brother' and 'sister' are there then read and filter.

I have below code:

for data in list:
    file= data[2]
    text_file= open(file,'r').readlines()
    if data[0], data[1] in text_file:
    #do something..

The above code is not giving me a proper output as per the requirement. Can kindly someone help me with this approach?

Thanks!

Answer 1

This is how I have done it:

lis=[[('dad', 'mom', 'test1.txt')],
    [('brother', 'sister', 'test2.txt')],
    [('uncle', 'aunty', 'test3.txt')],
    [('grandpa', 'grandma', 'test4.txt')]]
for i in range(len(lis)):
    for j in lis[j]:
        f = open(i[2])
        lines = f.read()
        if i[0] in lines and i[1] in lines:
            #do sth

I have iterated the elements of the list in the range of the length of the list: len(lis) . This way j takes the values 0, 1, 2, 3 . Then I have used a for loop which iterates through the elements of the list. Hence, j assumes values of the elements of lis as lis[0], lis[1], lis[2], lis[3] .

Now that j has values of the list elements, we can use i[(integer)] and access the elements of the elements of the list ie, "dad", "mom", "test1.txt" , etc.

Hence we can apply conditions to i[0] or i[1] etc.

For example:

if i[0] == "dad":
    print(something)

Hope this helps you!

Answer 2

Is not clear what's wrong for you since you read the correct file name 4 times

I suppose you have to exit the for loop if you find what you are looking for with break statement.

Answer 3

Try not to use keywords like list

L=[[('dad', 'mom', 'test1.txt')],
[('brother', 'sister', 'test2.txt')],
[('uncle', 'aunty', 'test3.txt')],
[('grandpa', 'grandma', 'test4.txt')]]
for data in L:
  f=data[0][2]
  file1=open(f,"r")
  text_file=file1.read()
  if(data[0][0] and data[0][1] in text_file):
     #do something

Answer 4

lis=[[('dad', 'mom', 'test1.txt')],
    [('brother', 'sister', 'test2.txt')],
    [('uncle', 'aunty', 'test3.txt')],
    [('grandpa', 'grandma', 'test4.txt')]]
for i in lis:
    data=i[0][2]
    f=open(data,'r')
    file=f.read()
    if (i[0][0] and i[0][1])in file:
        pass