This is an example PyPy server, that is part of a blog post on using GitHub (or other providers) as a PyPy Server
This file isn't used by pip (at least in my version), although the specification states that it is (I have omitted the python_hello package and it still works). It is still useful from a discoverability point of view though, and future versions of Pip may require it.
Pip will look for directories using the normalised name of your package ('python-hello' in this case instead of 'python_hello'). More details in the specification.