arr = [
    [1,2,3],
    [4,5,6],
    [7,8,9]
]

n = len(arr)
m = len(arr[0])
result = [[0] * n for i in range(m)]

for i in range(n):
    for j in range(m):
        result[j][n-i-1] = arr[i][j]

print(result)