How to create two dimensional list of characters from file?

Question

I need some simple help. I have file with content like this:

jdss
sdjk
nbjs

So there is unknown numbers of lines and unknown numbers of characters in every line but all of lines is the same length. I want to get a two dimensional list

[['j','d','s','s'],
['s','d','j','k'],
['n','b','j','s']]

how to do it in the simplest way? What I tried:

list = [[]]
for line in f:
    whichLine = 0
    for ch in line:
        list [whichLine].append(ch)
    list.append([])
    whichLine += 1

But it doesn't work like I want.

Answer 1

>>> [list(line) for line in f]
[['j', 'd', 's', 's'], ['s', 'd', 'j', 'k'], ['n', 'b', 'j', 's']]

Answer 2

list comprehension works well here.

my_list = [[c for c in line] for line in f]

(note its usually not a good idea to overwrite the name list)

if you don't want the newline characters

my_list = [[c for c in line.strip()] for line in f]