protected override Expression <Func <AttributeListCollectionAssociation, bool> > FindExisting(AttributeListCollectionAssociation record)
 => existing
 => existing.AttributeId == record.AttributeId &&
 existing.AttributeListCollectionId == record.AttributeListCollectionId;
        protected override IEnumerable <object> EnumerateReferences(AttributeListCollectionAssociation record)
        {
            yield return(record.Attribute);

            yield return(record.AttributeListCollection);
        }