def find_hosts_by_staleness(staleness, query):
    logger.debug("find_hosts_by_staleness(%s)", staleness)
    config = inventory_config()
    staleness_conditions = tuple(staleness_to_conditions(config, staleness, stale_timestamp_filter))
    if "unknown" in staleness:
        staleness_conditions += (Host.stale_timestamp == NULL,)

    return query.filter(or_(*staleness_conditions))
def staleness_filter(staleness):
    config = inventory_config()
    return staleness_to_conditions(config, staleness, _stale_timestamp_filter)