public function addNewInstance($object, FieldDescriptionInterface $fieldDescription)
    {
        $instance = $fieldDescription->getAssociationAdmin()->getNewInstance();
        $mapping = $fieldDescription->getAssociationMapping();

        $method = sprintf('add%s', Inflector::classify($mapping['fieldName']));

        if (!method_exists($object, $method)) {
            $method = rtrim($method, 's');

            if (!method_exists($object, $method)) {
                $method = sprintf('add%s', Inflector::classify(Inflector::singularize($mapping['fieldName'])));

                if (!method_exists($object, $method)) {
                    throw new \RuntimeException(
                        sprintf('Please add a method %s in the %s class!', $method, ClassUtils::getClass($object))
                    );
                }
            }
        }

        $object->$method($instance);
    }