comefrom: <qiyuangong>037_Sudoku_Solver_1.py
code: def is_safe( board, row, col, ch):
      for k in range(9):
          if board[k][col] == ch:
              return False
          if board[row][k] == ch:
              return False
      start_row, start_col = 3 * (row / 3), 3 * (col / 3)
      for i in range(start_row, start_row + 3):
          for j in range(start_col, start_col + 3):
              if board[i][j] == ch:
                  return False
      return True
masked: def sample_funcname ( var_0 , var_1 , var_2 , var_3 ) :
      for var_6 in range ( 9 ) :
          if var_0 [ var_6 ] [ var_2 ] == var_3 :
              return False
          if var_0 [ var_1 ] [ var_6 ] == var_3 :
              return False
      var_9 , var_10 = 3 * ( var_1 / 3 ) , 3 * ( var_2 / 3 )
      for var_11 in range ( var_9 , var_9 + 3 ) :
          for var_12 in range ( var_10 , var_10 + 3 ) :
              if var_0 [ var_11 ] [ var_12 ] == var_3 :
                  return False
      return True
  