WSGI server, server wont start

Im getting this warning and sometimes my server dose not run any chance someone knows how to help???

WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.

Hi,

Sounds like you’re using Python. You’ll likely want a package like Gunicorn to serve your app, as shown in the Django and Flask guides (you’ll need to add it to your dependencies/requirements.txt)

Alan