code: public function reverseTransform($modelData, PropertyPathInterface $propertyPath, $values)
      {
          if (!$modelData instanceof ProductInterface) {
              throw new \InvalidArgumentException(sprintf('Wrong entity passed "%s"', get_class($modelData)));
          }
          
          if ($this->isPhotoCollectionUnModified($values)) {
              return false;
          }
          
          $previousCollection = $this->propertyAccessor->getValue($modelData, $propertyPath);
          $this->clearPreviousCollection($previousCollection);
          
          $collection = $this->createPhotosCollection($modelData, $values);
          
          if (0 === $collection->count()) {
              $modelData->setPhoto(null);
          }
          
          $this->propertyAccessor->setValue($modelData, $propertyPath, $collection);
      }
docs: {@inheritdoc}