Update app.py

app.py

@@ -12,7 +12,7 @@ openai_models = ["gpt-4", "gpt-4-0613", "gpt-4-32k", "gpt-4-32k-0613", "gpt-3.5-
                      "gpt-3.5-turbo-0613", "gpt-3.5-turbo-16k", "gpt-3.5-turbo-16k-0613", "text-davinci-003", 
                      "text-davinci-002", "text-curie-001", "text-babbage-001", "text-ada-001"]
 
-def test_handler(optionSelection, prompt: str = TEST_MESSAGE, model):
+def test_handler(optionSelection, prompt: str = TEST_MESSAGE, model: str ="gpt-4"):
     match optionSelection:
         case  "OpenAI API":
             try: