Try to fix Type error

app.py

@@ -69,7 +69,8 @@ def handle_submit():
     else:
         st.session_state.conversation(f"<p><strong>Adrega AI:</strong>: Please enter a question.")
 
-#st.title("Adrega AI Help")
+if 'placeholder' not in st.session_state:
+    st.session_state.placeholder = st.empty()
 
 st.text_input('Ask me a question', key='user_input', on_change=handle_submit)
 col1, col2 = st.columns(2)
@@ -84,8 +85,5 @@ if 'conversation' not in st.session_state:
 with col2:
     st.session_state.include_context = st.checkbox('Search in Help')
 
-if 'placeholder' not in st.session_state:
-    st.session_state.placeholder = st.empty()
-
 st.session_state.placeholder
 #st.markdown(f'<div class="scrollable-div">{st.session_state.conversation}</div>', unsafe_allow_html=True)