Update app.py

app.py

@@ -71,7 +71,7 @@ def message_and_history(img, input, history, api_key):
     inp = '  '.join(s)
     output = api_calling(img,inp, api_key)
     if len(input) == 0:
-        history.append((,output))
+        history.append(('',output))
     else:
         history.append((input, output))
     return history, history