fixed error : Referenced before assignment (responses_df)

app.py

@@ -1309,8 +1309,8 @@ def main():
     # Parsed data
     parsed_tickbox = st.checkbox('Parsed Data')
     if parsed_tickbox:
-        if responses_df:
-            parsed_responses = filter_dataframe(responses_df)
+        if 'parsed_responses' in st.session_state:
+            parsed_responses = filter_dataframe(st.session_state['parsed_responses'])
             st.session_state['parsed_responses'] = parsed_responses
         else:
             parsed_responses = filter_dataframe(parsed)