from typing import TYPE_CHECKING, Dict, Optional

if TYPE_CHECKING:
    from zerver.tornado.event_queue import ClientDescriptor

descriptors_by_handler_id: Dict[int, "ClientDescriptor"] = {}


def get_descriptor_by_handler_id(handler_id: int) -> Optional["ClientDescriptor"]:
    return descriptors_by_handler_id.get(handler_id)


def set_descriptor_by_handler_id(handler_id: int, client_descriptor: "ClientDescriptor") -> None:
    descriptors_by_handler_id[handler_id] = client_descriptor


def clear_descriptor_by_handler_id(handler_id: int) -> None:
    del descriptors_by_handler_id[handler_id]