Introduce a TypedMapping (analog to TypedDict but frozen)

[tmk (Thomas Kehrenberg)]

There was some discussion about how to type frozendict here:

PEP 814: Add frozendict built-in type

Yes, we’ll have to think about how this new builtin type (if it is accepted) interacts with TypedDict. (“We” here doesn’t necessarily mean the authors of PEP 814; this is something we can add separately later.) Currently, TypedDict is specified as being restricted to instances of exactly dict: no subclasses, no other kinds of Mappings. So if we don’t change anything, frozendicts would not be compatible with TypedDict at all. A few options: Add class TD(TypedDict, frozen=True): (as Thomas sug…

I’m somewhat optimistic that frozendict can be provided as a backport pypi package to older Python version, so this will hopefully also help you.