Update app.py

app.py

@@ -131,7 +131,7 @@ def chat_gpt_ep(content: Text = None):
 def chat_gpt_stream_ep(content: Text = None):
     start_time = time.time()
     obj = json.loads(content.content)
-    response = openai.Completion.create(
+    response = openai.ChatCompletion.create(
         model='gpt-3.5-turbo',
         messages=obj['messages'],
         stream=True,  # this time, we set stream=True