Here are the extra steps done before running server.py with '--build' option for the first time successfully.
--- Update node version ---
$sudo npm cache clean -f
$sudo npm install -g n
$sudo n stable
$hash -r
elvis@goofy:/mnt$ node -v
v20.16.0
--- update pyopenssl version ---
pip3 install pyopenssl==24.0.0
--- Finally ---
$python3 server.py --insecure --build
-- reference ---
Github