Issue 20478 suggests ensuring that even weight/frequency mappings like collections.Counter are consistently handled as iterables in the current statistics module API.

However, it likely makes sense to provide public APIs that support efficiently working with such weight/frequency mappings directly, rather than requiring that they be expanded to a full iterable all the time.

One possibility would be to provide parallel APIs with the _map suffix, similar to the format() vs format_map() distinction in the string formatting APIs.