  set Streamlit to use that port, start Streamlit with the --server.port
  option:
bash
  streamlit run my_app.py --server.port=80
AWS EC2 server: First, click on your instance in the AWS Console.
  Then scroll down and click on Security Groups → Inbound → Edit. Next, add
  a Custom TCP rule that allows the Port Range 8501 with Source
0.0.0.0/0.
Other types of server: Check the firewall settings.
If that still doesn't solve the problem, try running a simple HTTP server
instead of Streamlit, and seeing if that works correctly. If it does, then
you know the problem lies somewhere in your Streamlit app or configuration (in
which case you should ask for help in our
forums!) If not, then it's definitely unrelated
to Streamlit.
How to start a simple HTTP server:
bash
python -m http.server [port]
