def __init__(
        self,
        access_key: str,
        secret_key: str,
        model_name: str,
        endpoint_url: str,
        context_window: int,
        llm_type: APIType = "chat",
    ) -> None:
        """
        Initialize a Qianfan LLM instance.

        :param access_key: The Access Key obtained from the Security Authentication Center
            of Baidu Intelligent Cloud Console.
        :param secret_key: The Secret Key paired with the Access Key.
        :param model_name: The name of the model service. For example: ERNIE-4.0-8K.
        :param endpoint_url: The chat endpoint URL of the model service.
            For example: https://aip.baidubce.com/rpc/2.0/ai_custom/v1/wenxinworkshop/chat/completions_pro .
        :param context_windows: The context window size. for example: 8192.
        :param llm_type: The LLM type. Currently, only the chat type is supported.
        """
        if llm_type != "chat":
            raise NotImplementedError("Only the chat type is supported.")

        super().__init__(
            model_name=model_name,
            endpoint_url=endpoint_url,
            context_window=context_window,
            access_key=access_key,
            secret_key=secret_key,
            llm_type=llm_type,
        )
        self._client = Client(access_key, secret_key)

        Initialize a Qianfan LLM instance.

        :param access_key: The Access Key obtained from the Security Authentication Center
            of Baidu Intelligent Cloud Console.
        :param secret_key: The Secret Key paired with the Access Key.
        :param model_name: The name of the model service. For example: ERNIE-4.0-8K.
        :param endpoint_url: The chat endpoint URL of the model service.
            For example: https://aip.baidubce.com/rpc/2.0/ai_custom/v1/wenxinworkshop/chat/completions_pro .
        :param context_windows: The context window size. for example: 8192.
        :param llm_type: The LLM type. Currently, only the chat type is supported.
        
llama-index-integrations/llms/llama-index-llms-qianfan/llama_index/llms/qianfan/base.py