There is a project called pytest-smtpd that I find really useful to test applications relying on SMTP. It allows to actually send message over the network, and not mock calls, and then users can check on the server which messages have actually been sent. Additionally, it allows to test various authentication scenarios.

I would love to find a similar tool for the SMPP protocol. I could not find any server implementation on PyPI. Do you people know of such implementations?

If not, how hard would it be to implement it with python-smpplib?