public Guid BuildPort(MathIdentifier entityId, InstanceIdSet inputSignals, InstanceIdSet outputSignals, InstanceIdSet buses)
{
IEntity entity = Service <ILibrary> .Instance.LookupEntity(entityId);
Port p = entity.InstantiatePort(MapSignals(inputSignals), MapSignals(outputSignals), MapBuses(buses));
_system.AddPort(p);
return(p.InstanceId);
}