Several things done:
1. Replace all occurrences of `Any` by respective concrete types.
2. Make `Shelf` and its subclassses generic. (Fixes#5815)
3. `shelve.open` should return a general `Shelf` object, not `DbfilenameShelf`. The documentation does not expose such implementation detail.
4. The argument `dict` is annotated with an abstract type `MutableMapping` rather than concrete type `Dict`.
5. Remove unnecessary methods. Some of them are inherited from `MutableMapping`, so no need to repeat them here.
6. Use builtin-in generics instead of importing from `typing`.
This is enough to get stubtest working (note that it's a little annoying
to install mypy currently since typed-ast seems to have broken again on
Python 3.10)
Co-authored-by: hauntsaninja <>
