def _mac_address(self, queryset, value):
    value = value.strip()
    if (not value):
        return queryset
    try:
        return queryset.filter(interfaces__mac_address=value).distinct()
    except AddrFormatError:
        return queryset.none()
def _mac_address(self, queryset, value):
    value = value.strip()
    if (not value):
        return queryset
    try:
        return queryset.filter(interfaces__mac_address=value).distinct()
    except AddrFormatError:
        return queryset.none()