langchain/document_loaders/slack_directory.py/SlackDirectoryLoader/load
class SlackDirectoryLoader:    def load(self) -> List[Document]:
        """Load and return documents from the Slack directory dump."""
        docs = []
        with zipfile.ZipFile(self.zip_path, "r") as zip_file:
            for channel_path in zip_file.namelist():
                channel_name = Path(channel_path).parent.name
                if not channel_name:
                    continue
                if channel_path.endswith(".json"):
                    messages = self._read_json(zip_file, channel_path)
                    for message in messages:
                        document = self._convert_message_to_document(
                            message, channel_name
                        )
                        docs.append(document)
        return docs