def twin(self):
        j = 0
        for i in range(self.N):
            if (self.board[i][j] != " ") and (self.board[i][j + 1] != " "):
                print(self.board)
                localBoard = self.board
                localBoard[i][j], localBoard[i][j + 1] = localBoard[i][j + 1], localBoard[i][j]
                print(localBoard.ravel())
                print(localBoard.ravel().tolist())
                return Board(localBoard.ravel())