async def adelete_messages(self, key: str) -> Optional[list[ChatMessage]]:
        """Async version of Delete messages for a key."""
        async with self._async_session() as session:
            await session.execute(delete(self._table_class).filter_by(key=key))
            await session.commit()
        return None
Async version of Delete messages for a key.
llama-index-integrations/storage/chat_store/llama-index-storage-chat-store-postgres/llama_index/storage/chat_store/postgres/base.py