Update app.py

app.py

@@ -46,6 +46,7 @@ async def speech_to_text(file: UploadFile = File(...)):
 
 @app.post("/tts/")
 def text_to_speech(input_text: TextInput):
+    instance = ggwave.init()
     """Convert text to a WAV audio file using ggwave and return as response."""
     encoded_waveform = ggwave.encode(instance, input_text.text)
     buffer = io.BytesIO()