@receiver((post_save, post_delete), sender=CircuitTermination)
def update_circuit(instance, **kwargs):
 Circuit.objects.filter(pk=instance.circuit_id).update(last_updated=timezone.now())

@ receiver ( ( post_save , post_delete ) , sender = CircuitTermination ) def update_circuit ( instance , ** kwargs ) : Circuit . objects . filter ( pk = instance . circuit_id ) . update ( last_updated = timezone . now ( ) )
when a circuittermination has been modified .