Fix python generator error

app.py

@@ -63,7 +63,8 @@ def respond(
     for m in history:
         messages.append({"role": m["role"], "content": m["content"]})
     messages.append({"role": "user", "content": message})
-    return infer(messages, max_tokens, temperature, top_p)
+    for response in infer(messages, max_tokens, temperature, top_p):
+        yield response
 
 app = gr.ChatInterface(
     respond,