transpose matrix in python without numpy

1def transpose(matrix):
2    rows = len(matrix)
3    columns = len(matrix[0])
4
5    matrix_T = []
6    for j in range(columns):
7        row = []
8        for i in range(rows):
9           row.append(matrix[i][j])
10        matrix_T.append(row)
11
12    return matrix_T
13