langchain/tools/azure_cognitive_services/text2speech.py/AzureCogsText2SpeechTool/_text2speech
class AzureCogsText2SpeechTool:    def _text2speech(self, text: str, speech_language: str) -> str:
        try:
            import azure.cognitiveservices.speech as speechsdk
        except ImportError:
            pass

        self.speech_config.speech_synthesis_language = speech_language
        speech_synthesizer = speechsdk.SpeechSynthesizer(
            speech_config=self.speech_config, audio_config=None
        )
        result = speech_synthesizer.speak_text(text)

        if result.reason == speechsdk.ResultReason.SynthesizingAudioCompleted:
            stream = speechsdk.AudioDataStream(result)
            with tempfile.NamedTemporaryFile(
                mode="wb", suffix=".wav", delete=False
            ) as f:
                stream.save_to_wav_file(f.name)

            return f.name

        elif result.reason == speechsdk.ResultReason.Canceled:
            cancellation_details = result.cancellation_details
            logger.debug(f"Speech synthesis canceled: {cancellation_details.reason}")
            if cancellation_details.reason == speechsdk.CancellationReason.Error:
                raise RuntimeError(
                    f"Speech synthesis error: {cancellation_details.error_details}"
                )

            return "Speech synthesis canceled."

        else:
            return f"Speech synthesis failed: {result.reason}"