Changing of port and multiple streamlit app

Here is some solutions to the Permission denied : https://serverfault.com/questions/112795/how-to-run-a-server-on-port-80-as-a-normal-user-on-linux
I found the “redir” solution the most convenient for testing :
sudo redir --laddr=127.0.0.1 --lport=80 --caddr=127.0.0.1 --cport=8501