code: SimpleRelation buildSimpleOneToOneOneToOne(Entity entity, final Attribute fromAttribute, Entity targetEntity, Attribute targetAttribute) {
          Namer targetNamer = relationUtil.getOneToOneNamer(fromAttribute, targetEntity.getModel());
          Namer inverseNamer = relationUtil.getInverseOneToOneNamer(fromAttribute, entity.getModel());
          SimpleRelation o2o = new SimpleOneToOne(inverseNamer, targetNamer, fromAttribute, entity, targetEntity, targetAttribute) {
  
              @Override
              protected AbstractRelation buildInverse() {
                  SimpleOneToOne invo2o = new SimpleOneToOne(getTo(), getFrom(), getToAttribute(), getToEntity(), getFromEntity(), fromAttribute);
                  OneToOneConfig iso2oConfig = getFromAttribute().getColumnConfig().getInverseOneToOneConfig();
                  setLabelSingular(iso2oConfig, invo2o);
                  configureActions(invo2o, cfg().getDefaultInverseOneToOneConfig(), iso2oConfig);
                  return invo2o;
              }
          };
  
          OneToOneConfig o2oConfig = fromAttribute.getColumnConfig().getOneToOneConfig();
          setLabelSingular(o2oConfig, o2o);
  
          configureActions(o2o, cfg().getDefaultOneToOneConfig(), o2oConfig);
          return o2o;
      }
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