Update app.py

app.py

@@ -462,7 +462,7 @@ def ask_df(df, api_key, model, ui_session_id):
         answers.append(complete_answer)
         print(complete_answer)
     df[question_column] = answers
-    return df, source
+    return df, sources_file
 
 def export_df(df, ftype):
     fname=secrets.token_urlsafe(16)