gh-141510: Use frozendict in the stdlib by vstinner · Pull Request #144909 · python/cpython

vstinner

If someone really want/need to modify one of the frozendict, it remains possible. Example: platform._ver_stages |= frozendict(final=60)

$ ./python
>>> import platform
>>> platform._ver_stages
frozendict({'dev': 10, 'alpha': 20, 'a': 20, 'beta': 30, ..., 'p': 200})

>>> platform._ver_stages['final']=60
...
TypeError: 'frozendict' object does not support item assignment

>>> platform._ver_stages |= frozendict(final=60)
>>> platform._ver_stages
frozendict({'dev': 10, 'alpha': 20, 'a': 20, 'beta': 30, ..., 'p': 200, 'final': 60})

The purpose of this change is more to catch dictionaries modified by accident.