Update app.py

app.py

@@ -123,7 +123,7 @@ class EnglishTutor:
         if text.startswith('"') and text.endswith('"'):
             text = text[1:-1]
             
-        tts_prompt = {text}
+        tts_prompt = text  # Remove the curly braces that were creating a set
         tts_emotion = "Warm, encouraging, and clear with a friendly and supportive tone."
 
         return TTS_CLIENT.predict(