new_contents: #!/usr/bin/env python3
  
  def rotate(arr):
      new_arr = []
      for i in range(len(arr)-1, -1, -1):
          new_arr.append([arr[x][i] for x in range(len(arr))])
      return new_arr
  
  #TODO(Wesley) inplace version
  
  if __name__ == "__main__":
      i = [[1,2,3],
           [4,5,6],
           [7,8,9]]
      assert rotate(i) == [[3,6,9],[2,5,8],[1,4,7]]
      print("Tests passed")
  
subject: Add CTCI 1.7