Gets a board with the position of the node.

        It's a copy, so modifying the board will not alter the game.

def board(self, *, _cache: bool = True) -> chess.Board:
        """
        Gets a board with the position of the node.

        It's a copy, so modifying the board will not alter the game.
        """
        if self.board_cached is not None:
            board = self.board_cached()
            if board is not None:
                return board.copy()

        board = self.parent.board(_cache=False)
        board.push(self.move)

        if _cache:
            self.board_cached = weakref.ref(board)
            return board.copy()
        else:
            return board