Transpose of a matrix using Python 3.8

Question

What is the transpose of a matrix:
In linear algebra, the transpose of a matrix is an operator which flips a matrix over its diagonal; that is, it switches the row and column indices of the matrix A by producing another matrix, often denoted by Aᵀ.
Code
dimension = int(input())
matrix = []
transpose = []
for row in range(dimension):
    entry = list(map(int,input().split()))
    matrix.append(entry)
for i in range(dimension):
    for j in range(dimension):
        transpose.append(matrix[j][i])
m = 0
n = dimension

for x in range(dimension+1):
    
    row = transpose[m:n]
    list1 = [str(item) for item in row]
    string2 = " ".join(list1)
    print(string2)
    m = n
    n = n + dimension

My question
What all modifications I can do to this code to make it better furthermore efficient?

superb rain · Answer

You're converting the matrix elements to int and then back to string without doing anything with the ints, so that's just wasteful.
Anyway, the usual way to transpose is zip. Demo including mock input:
input = iter('''3
1 2 3
4 5 6
7 8 9'''.splitlines()).__next__

matrix = [input().split() for _ in range(int(input()))]

for column in zip(*matrix):
    print(*column)

Output:
1 4 7
2 5 8
3 6 9

Jorge Morgado · Answer

You could do something like this:
dimension = int(input())
matrix = [list(map(int,input().split())) for _ in range(dimension)]
transpose = [[matrix[j][i] for j in range(dimension)] for i in range(dimension)]

PD: This still has to pass by every item on the matrix but it is a little more compact code, and if you're used to python you could find it a little more legible.

Transpose of a matrix using Python 3.8

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