Experiments with sudoku validation (Mostly playing with list comprehensions and generators)

sudoku.py

board = [
    [1,2,3,4,5,6,7,8,9],
    [5,7,8,1,3,9,6,2,4],
    [4,9,6,8,7,2,1,5,3],
    [9,5,2,3,8,1,4,6,7],
    [6,4,1,2,9,7,8,3,5],
    [3,8,7,5,6,4,2,9,1],
    [7,1,9,6,2,3,5,4,8],
    [8,6,4,9,1,5,3,7,2],
    [2,3,5,7,4,8,9,1,6]
]

size = 9
block_size = 3

wanted = set([x for x in range(1, size + 1)])

def blocks(board):
    # iterate in 3x3 blocks starting @ 0,3,6 in the x & y
    for x, y in ((x,y)
                 for y in range(0, size, block_size)
                 for x in range(0, size, block_size)):
        yield [board[by][bx]
               for by in range(y, y + block_size)
               for bx in range(x, x + block_size)]


def is_solved(board):
    # check rows have 1-9
    for row in board:
        if wanted != set(row):
            return False
    # zip subarrays to make columns and check also
    for col in zip(*board):
        if wanted != set(col):
            return False
    # check the 3x3 blocks to ensure they are also good.
    for block in blocks(board):
        if wanted != set(block):
            return False
    # its a valid solution!
    return True

print(is_solved(board))