code: def create_articles(self, project, articleset, json_data=None, **options):
          
          url = URL.article.format(**locals())
          # TODO duplicated from create_set, move into requests
          # (or separate post method?)
          if json_data is None:
              # form encoded request
              return self.request(url, method="post", data=options)
          else:
              if not isinstance(json_data, string_types):
                  json_data = json.dumps(json_data, default=serialize)
              headers = {'content-type': 'application/json'}
              return self.request(url, method='post', data=json_data, headers=headers)
docs: Create one or more articles in the set. Provide the needed arguments
          using the json_data or with key-value pairs
          @param json_data: A dictionary or list of dictionaries. Each dict
                            can contain a 'children' attribute which
                            is another list of dictionaries.