@classmethod
def sort(cls, runs, order_by_list):
    """Sorts a set of runs based on their natural ordering and an overriding set of order_bys.
        Runs are naturally ordered first by start time descending, then by run id for tie-breaking.
        """
    runs = sorted(runs, key=lambda run: (-run.info.start_time, run.info.
        run_uuid))
    if not order_by_list:
        return runs
    for order_by_clause in reversed(order_by_list):
        key_type, key, ascending = cls.parse_order_by(order_by_clause)
        runs = sorted(runs, key=lambda run: cls._get_value_for_sort(run,
            key_type, key, ascending), reverse=not ascending)
    return runs
