old_contents: 
  class Cell:
      """
      Cell class to represent a cell in the game board
  
      It stores all data(markers, states) of a cell
      """
      def __init__(self):
          self._isMine = False #the cell is a mine or not
          self._isRevealed = False #the cell is revealed by player or not
          self._isFlagged = False #the cell is flagged by player or not
          self._minesAround = 0 #the mines around current cell [0, 8] (upper left, upper, upper right, left, right, down left, down, down right)
  
  class Game:
      """
      Game class represent a game board
      Game holds a board of 2D cells, and all states (game done or game ongoing...)
      """
      def __init__(self, rows, cols, minesNumber):
          self._rows = rows
          self._cols =cols
          self._minesNumber = minesNumber #The number of mines the board holds
          self._board = [] #The size of this board should be rows*cols
          self._mines = [] #A list of cells which are mines
          self._result = 0 #Game result [0:game ongoing, 1:player win, -1: player lose]
          self._start_time = ""
          self._end_time = ""
  
  class Player:
      """
      Player: every player has their game history, current game status
      """
      def __init__(self, name):
          self._history = []
          self._name = name
  
new_contents: 
  class Cell:
      """
      Cell: represent a single cell on the game board
  
      It stores all data(markers, states) of a cell
      """
      def __init__(self):
          self._isMine = False #Cell is a mine or not
          self._isRevealed = False #Cell is revealed by player or not
          self._isFlagged = False #Cell is flagged by player or not
          self._minesAround = 0 #The number of mines around a cell, range is [0, 8]
  
  class Game:
      """
      Game: represent a single game
  
      Game holds a board of 2D cells, and all states (game done or game ongoing...)
      """
      def __init__(self, rows, cols, minesNumber, player):
          self._rows = rows
          self._cols =cols
          self._minesNumber = minesNumber #The number of mines the board holds
          self._board = [] #The size of this board should be rows*cols
          self._mines = [] #A list of cells which are mines
          self._result = 0 #Game result [0:game ongoing, 1:player win, -1: player lose]
          self._start_time = ""
          self._end_time = ""
          self._player = player
  
  class Player:
      """
      Player: every player has their game history, current game status
      """
      def __init__(self, name, game):
          self._name = name
          self._history = [] #If game finished, add game to history
          self._game = game #Current game which the player is working on
  
subject: fix model