Update app.py

app.py

@@ -7,7 +7,7 @@ openai.api_key = os.getenv('OpenAPI')
 
 chat_history = ""
 
-def call_openai_api(user_prompt, stream=true):
+def call_openai_api(user_prompt, stream='true'):
     global chat_history 
 
     text = """