code: protected Optional<FormYourCollectionResource> findListableYourCollection(PropertyDesc pd, FormMappingOption option) {
          final Class<?> propertyType = pd.getPropertyType();
          final List<FormYourCollectionResource> yourCollections = option.getYourCollections();
          return yourCollections.stream() // checking defined type and instance type
                  .filter(res -> propertyType.equals(res.getYourType())) // just type in form mapping (to avoid complexity)
                  .filter(res -> res.getYourCollectionCreator().apply(Collections.emptyList()) instanceof List)
                  .findFirst(); // basically only-one here (if no duplicate type specified)
      }
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