def test_subset_valid_block():
board = Board(VALID_BOARD_ARR)
assert is_subset_valid(board.get_block(0, 1)) is True
def test_board_get_blocks():
board = Board(EMPTY_BOARD_ARR)
assert np.array_equal(board.get_block(1, 2),
np.array([[7, 0, 4], [0, 0, 0], [0, 0, 0]]))