langchain/document_loaders/joplin.py/JoplinLoader/_get_notes
class JoplinLoader:    def _get_notes(self) -> Iterator[Document]:
        has_more = True
        page = 1
        while has_more:
            req_note = urllib.request.Request(self._get_note_url.format(page=page))
            with urllib.request.urlopen(req_note) as response:
                json_data = json.loads(response.read().decode())
                for note in json_data["items"]:
                    metadata = {
                        "source": LINK_NOTE_TEMPLATE.format(id=note["id"]),
                        "folder": self._get_folder(note["parent_id"]),
                        "tags": self._get_tags(note["id"]),
                        "title": note["title"],
                        "created_time": self._convert_date(note["created_time"]),
                        "updated_time": self._convert_date(note["updated_time"]),
                    }
                    yield Document(page_content=note["body"], metadata=metadata)

                has_more = json_data["has_more"]
                page += 1