def room_description(adv):
    """Provide room description.

    Args:
        adv:    namedtuble holding the game data

    Modifies:   nothing

    Returns:
        string: short name or long description of room or too dark message
    """
    location = adv.rooms[adv.player["location"]]
    if "visible" in location["status"]:
        if "verbose" in adv.player["status"]:
            return location["long"]
        if "short" in adv.player["status"] or "visited" in location["status"]:
            return adv.player["location"].capitalize() + "."
        return location["long"]
    return adv.messages["toodark"]