langchain/document_loaders/telegram.py/TelegramChatApiLoader/_combine_message_texts
class TelegramChatApiLoader:    def _combine_message_texts(
        self, message_threads: Dict[int, List[int]], data: pd.DataFrame
    ) -> str:
        """
        Combine the message texts for each parent message ID based \
            on the list of message threads.

        Args:
            message_threads (dict): A dictionary where the key is the parent message \
                ID and the value is a list of message IDs in ascending order.
            data (pd.DataFrame): A DataFrame containing the conversation data:
                - message.sender_id
                - text
                - date
                - message.id
                - is_reply
                - reply_to_id

        Returns:
            str: A combined string of message texts sorted by date.
        """
        combined_text = ""

        # Iterate through sorted parent message IDs
        for parent_id, message_ids in message_threads.items():
            # Get the message texts for the message IDs and sort them by date
            message_texts = (
                data[data["message.id"].isin(message_ids)]
                .sort_values(by="date")["text"]
                .tolist()
            )
            message_texts = [str(elem) for elem in message_texts]

            # Combine the message texts
            combined_text += " ".join(message_texts) + ".\n"

        return combined_text.strip()