text: class Solution(object):
      def rotate(self, matrix):
          """
          :type matrix: List[List[int]]
          :rtype: None Do not return anything, modify matrix in-place instead.
          """
          matrix.reverse()
          for i in range(len(matrix)):
              for j in range(i):
                  matrix[i][j], matrix[j][i] = matrix[j][i], matrix[i][j]