change csv to tsv in file download

app.py

@@ -150,10 +150,10 @@ if __name__ == "__main__":
         st.subheader('Output data')
         st.write(df)
 
-        output_file = st.text_input("Enter name for the file to be downloaded", value="cards_output.csv")
+        output_file = st.text_input("Enter name for the file to be downloaded", value="cards_output.tsv")
         if output_file is not None:
             csv = convert_df(df)
-            st.download_button("Download data as CSV", csv, file_name=output_file)
+            st.download_button("Download data as tab-separated values", csv, file_name=output_file)