Implement `check(board)` for a 9-cell board (list of strings, "" for empty). Run it on these five boards — three canonical wins/draw plus two boundary cases — and print the result for each: ["X","X","X","","O","","O","",""] # X wins top row (canonical) ["X","O","X","O","X","O","O","X","O"] # draw — board full, no line ["X","O","","X","O","","X","",""] # X wins left column ["","","","","","","","",""] # boundary: empty board → None ["O","X","X","X","O","","X","","O"] # boundary: O wins diagonal 0-4-8 Expected: X draw X None O