def output_keys(self) -> List[str]:
        """Will always return text key.
        :meta private:
        """
        return [self.output_key]
    @root_validator()
    def validate_environment(cls, values: Dict) -> Dict:
        """Validate that api key and python package exists in environment."""
        try:
            from bs4 import BeautifulSoup  # noqa: F401
        except ImportError:
            raise ValueError(
                "Could not import bs4 python package. "
                "Please install it with `pip install bs4`."
            )
        return values
    def _call(
        self,
        inputs: Dict[str, Any],
        run_manager: Optional[CallbackManagerForChainRun] = None,
    ) -> Dict[str, Any]:
        from bs4 import BeautifulSoup
        _run_manager = run_manager or CallbackManagerForChainRun.get_noop_manager()
        # Other keys are assumed to be needed for LLM prediction
        other_keys = {k: v for k, v in inputs.items() if k != self.input_key}
        url = inputs[self.input_key]
        res = self.requests_wrapper.get(url)
        # extract the text from the html
        soup = BeautifulSoup(res, "html.parser")
        other_keys[self.requests_key] = soup.get_text()[: self.text_length]
        result = self.llm_chain.predict(
            callbacks=_run_manager.get_child(), **other_keys
        )
        return {self.output_key: result}
    @property
    def _chain_type(self) -> str:
        return "llm_requests_chain"