Update app.py

app.py

@@ -32,7 +32,7 @@ if 'badges' not in st.session_state:
 def generate_ai_response(user_input, level):
     prompt = f"Continue the story in a way that is engaging and suitable for a {level.lower()} English learner.\n\nStory so far:\n{''.join(st.session_state.story)}\nUser input: {user_input}\nAI continuation:"
     response = openai.Completion.create(
-        engine='gpt-4o-mini'
+        engine='gpt-4o-mini',
         prompt=prompt,
         max_tokens=100,
         temperature=0.7,