code: def _validate_player(player):
      '''
      Checks that a player is a valid player. Valid players are: 0, 1, 2, and 3.
  
      :param int player: player to be validated
      :return: None
      :raises NoSuchPlayerException: if the player is invalid
      '''
      valid_players = range(4)
      if player not in valid_players:
          valid_players = ', '.join(str(p) for p in valid_players)
          raise dominoes.NoSuchPlayerException('{} is not a valid player. Valid players'
                                               ' are: {}'.format(player, valid_players)f _validate_player(player):
      '''
      Checks that a player is a valid player. Valid players are: 0, 1, 2, and 3.
  
      :param int player: player to be validated
      :return: None
      :raises NoSuchPlayerException: if the player is invalid
      '''
      valid_players = range(4)
      if player not in valid_players:
          valid_players = ', '.join(str(p) for p in valid_players)
          raise dominoes.NoSuchPlayerException('{} is not a valid player. Valid players'
                                               ' are: {}'.format(player, valid_players))
docs: Checks that a player is a valid player. Valid players are: 0, 1, 2, and 3.
  
      :param int player: player to be validated
      :return: None
      :raises NoSuchPlayerException: if the player is invalid