AoC 2020 D17: Conway Cubes

def evolve(active: set[Point], get_neighbors: Callable[[Point], list[Point]]) -> set[Point]:
    new_active = set[Point]()
    candidates = active.union(
        neighbor for p in active for neighbor in get_neighbors(p)
    )
    for p in candidates:
        active_neighbors = sum(
            (neighbor in active) for neighbor in get_neighbors(p)
        )
        if p in active and should_stay_active(active_neighbors):
            new_active.add(p)
        elif p not in active and should_become_active(active_neighbors):
            new_active.add(p)
    return new_active

Point = TypeVar("Point", bound=tuple[int, ...])


def solve(
    points: set[Point],
    n: int,
    neighbors: Callable[[Point, bool], Generator[Point, Any, None]],
):
    alive = set(points)
    for _ in range(n):
        new_alive = set[Point]()
        for p in itertools.chain.from_iterable(neighbors(p, True) for p in alive):
            alive_neighbors = sum(np in alive for np in neighbors(p, False))
            if p in alive and alive_neighbors == 2 or alive_neighbors == 3:
                new_alive.add(p)
        alive = new_alive
    print(len(alive))