2.编写一函数，将N*N方阵行列互换。

答案：可以使用下面的函数来实现N*N方阵行列互换：
def swap_row_col(matrix):
m, n = len(matrix), len(matrix[0])

# Create an empty result matrix
result = [[0 for x in range(m)] for y in range(n)]

# traverse each element of the matrix
for i in range(m):
for j in range(n):
result[j][i] = matrix[i][j]

return result