workaround for unbound var handling

app.py

@@ -16,6 +16,7 @@ examples = [["how are you?"], ["hello"]]
 
 def chat_generate(word):
 #   print(f"**current reply")
+  global prev_chat
   p = prompt + prev_chat + "\n" + "you: " + word.lower() + "\n" + "me: "
   print(f"*****Inside chat_generate - Prompt is :{p}")
   json_ = {"inputs": p,