langchain/document_loaders/chatgpt.py/ChatGPTLoader/load
class ChatGPTLoader:    def load(self) -> List[Document]:
        with open(self.log_file, encoding="utf8") as f:
            data = json.load(f)[: self.num_logs] if self.num_logs else json.load(f)

        documents = []
        for d in data:
            title = d["title"]
            messages = d["mapping"]
            text = "".join(
                [
                    concatenate_rows(messages[key]["message"], title)
                    for idx, key in enumerate(messages)
                    if not (
                        idx == 0
                        and messages[key]["message"]["author"]["role"] == "system"
                    )
                ]
            )
            metadata = {"source": str(self.log_file)}
            documents.append(Document(page_content=text, metadata=metadata))

        return documents