Update app.py

app.py

@@ -747,6 +747,7 @@ elif st.session_state.current_index == len(st.session_state.data):
     st.write(f"**Thank you for taking part in this study!** \n ")
     c1, c2, c3 = st.columns([1,5,2])
     step = st.session_state.step
+    total_steps = len(STEPS)
     with c1:
         if st.button("<< Previous"):
             if step > 0: