code: public function submitArticle(Article $article): \One\Model\Article
      {
          $responseArticle = $this->post(
              self::ARTICLE_ENDPOINT,
              $this->normalizePayload(
                  $article->getCollection()
              )
          );
  
          $responseArticle = json_decode($responseArticle, true);
          $article->setId((string) $responseArticle['data']['id']);
  
          foreach ($article->getPossibleAttachment() as $field) {
              if ($article->hasAttachment($field)) {
                  foreach ($article->getAttachmentByField($field) as $attachment) {
                      $this->submitAttachment(
                          $article->getId(),
                          $attachment,
                          $field
                      );
                  }
              }
          }
  
          return $article;
      }
docs: submitting article here, return new Object cloned from original