langchain/llms/google_palm.py/GooglePalm/_agenerate
class GooglePalm:    async def _agenerate(
        self,
        prompts: List[str],
        stop: Optional[List[str]] = None,
        run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
    ) -> LLMResult:
        raise NotImplementedError()