check each box for boxx in ( ) for boxy in ( ) boxnumbers [ for in range(box_length) for in range(box_length) number self grid[(boxx xboxy ) boxnumbers append(number if not self _iscompletesetofnumbers(boxnumbers) return false return true print('''sudoku puzzleby al sweigart al@inventwithpython com sudoku is number placement logic puzzle game sudoku grid is grid of numbers try to place numbers in the grid such that every row columnand box has the numbers through once and only once for examplehere is starting sudoku grid and its solved form ++++ -- ++++ ''' input('press enter to begin ' load the sudokupuzzles txt file with open('sudokupuzzles txt'as puzzlefile puzzles puzzlefile readlines( remove the newlines at the end of each puzzle for ipuzzle in enumerate(puzzles) puzzles[ipuzzle strip( grid sudokugrid(random choice(puzzles) while truemain game loop grid display( check if the puzzle is solved if grid issolved() print('congratulationsyou solved the puzzle!' print('thanks for playing!' sys exit( project #