Immutables

New Features

* Add support for Python 3.10 and more tests
(by vstinner in 45105ecd for 46, hukkinj1 in d7f3eebb, f0b4fd40)

* Make `__repr__` more similar to other mapping types
(by ofek in 8af15021 for 17)

Misc

* Minor docs and CI fixes
(by MisterKeefe in 76e491cf for 32, fantix in 1282379d for 39)

* Allow `None` to be used as key in pure-Python implementation.

Bugfixes

* Various improvements w.r.t. type annotations & typing
support (by hukkinj1)

* Fix pure-Python implementation to accept keyword argument
"col" correctly (by hukkinj1)

Bug Fixes
=======

* Fix the mutation API to maintain elements count correctly (25, 24)

* Don't allow MapMutation.update() calls after the mutation is finished

* Simplify MapMutation.__exit__() implementation

* Add new `MapMutation.update()` method that behaves like
`MutableMapping.update()`

* Make it faster to create a `Map()` from another `Map()`—it's now an
O(1) operation.

* `update()` method had a bug that could cause the update `Map` object to
have a wrong number of elements.