You wrote a cool network client or server. It encrypts connections using TLS. Your test suite needs to make TLS connections to itself. Uh oh. Your test suite probably doesn't have a valid TLS certificate. Now what? trustme is a tiny Python package that does one thing: it gives you a fake certificate authority (CA) that you can use to generate fake TLS certs to use in your tests. Well, technically they're real certs, they're just signed by your CA, which nobody trusts. But you can trust it. Trust me. WWW: https://github.com/python-trio/trustme