Update app.py

app.py

@@ -105,9 +105,9 @@ with st.form('mform', clear_on_submit=False):
                 selected_df = pd.DataFrame()
                 pass
         st.success('Feature vector successfully created.')
-
+selected_df = selected_df.astype(str)
 with st.form("download_form", clear_on_submit=False):
     st.text_input("Enter filename", key="filename")
-    submit = st.form_submit_button("Download", on_click=selected_df,sleep=0)
+    submit = st.form_submit_button("Download", on_click=selected_df)