On Wed, Jan 5, 2022 at 5:29 AM Marco Sulla <marco.sulla.pyt...@gmail.com> wrote: > > $ python > Python 3.10.0 (heads/3.10-dirty:f6e8b80d20, Nov 18 2021, 19:16:18) > [GCC 10.1.1 20200718] on linux > Type "help", "copyright", "credits" or "license" for more information. > >>> a = {1:2} > >>> c = {1:2, 3:4} > >>> c.keys() - a.keys() > {3} > >>> >
Let's start with this. >>> a = {1} >>> c = {1, 3} >>> c - a {3} Do you agree that this should be a set? If so, then the next question is: should the keys view be considered frozen or not? Remember the set of keys can change (when the underlying dict changes). It's not difficult to construct a frozenset from a set. ChrisA -- https://mail.python.org/mailman/listinfo/python-list