Trio has great tools for dealing with some of the minutiae of making a polished Python package in general, but they're private; libraries that depend on Trio need to copy-paste or reimplement these tools if they want to offer equivalent functionality. If they reimplement, they probably won't do as good of a job.

I think we should add a new public Trio submodule (trio.libtools?) which provides:

• From trio._util: Final, NoPublicConstructor, generic_function, fixup_module_metadata, async_wraps, ConflictDetector
• A factory for creating modules like trio._deprecate, substituting a project's own deprecation warning, issue URL, and name.