langchain/document_loaders/twitter.py/TwitterTweetLoader/_format_tweets
class TwitterTweetLoader:    def _format_tweets(
        self, tweets: List[Dict[str, Any]], user_info: dict
    ) -> Iterable[Document]:
        """Format tweets into a string."""
        for tweet in tweets:
            metadata = {
                "created_at": tweet["created_at"],
                "user_info": user_info,
            }
            yield Document(
                page_content=tweet["text"],
                metadata=metadata,
            )