def METHOD_NAME(room_id, user_id):
    room = rooms_data.get(room_id, _get_empty_room())
    room["people"] = list(set(room["people"]) - {user_id})
    if len(room["people"]) > 0:
        rooms_data[room_id] = room
    else:
        del rooms_data[room_id]
    emit("preview-room:room-people-updated", room, room=room_id)