transpose_matrix.py

matrix = [
  [1,2,3],
  [4,5,6]
]

def transpose(matrix: list) -> list:
  if len(matrix) == 0:
    return []
  rows, cols = len(matrix), len(matrix[0])
  new_matrix = [[None] * rows for i in range(cols)]
  for r in range(rows):
    for c in range(cols):
      new_matrix[c][r] = matrix[r][c]
  return new_matrix


print(transpose(matrix))