'Return mirrors reverse-sorted by lag time.
The \'slowest\' mirror determines the best update that occurred on a
given replication target.'

def _filter_and_sort_mirrors(self, mirrors, flexvols):

    filtered_mirrors = [x for x in mirrors if (x.get('destination-volume') in flexvols)]
    sorted_mirrors = sorted(filtered_mirrors, key=(lambda x: int(x.get('lag-time'))), reverse=True)
    return sorted_mirrors
