@register.filter
def timesince_sortable(dt):
    delta = dt - timezone.now()
    # timedelta.total_seconds() not supported on python < 2.7
    seconds = delta.seconds + (delta.days * 24 * 3600)
    return mark_safe("<span data-seconds=\"%d\">%s</span>" %
                     (seconds, timesince(dt)))
dataset/ETHPy150Open CiscoSystems/avos/horizon/utils/filters.py/timesince_sortable/swapped operands of `-`