On Sat, Jul 25, 2020 at 12:58 PM Guido van Rossum <guido@python.org> wrote:
On Sat, Jul 25, 2020 at 12:45 PM Marco Sulla <Marco.Sulla.Python@gmail.com> wrote:
I also remembered another possible use-case: kwargs in CPython. In C code, kwargs are PyDictObjects. I suppose they are usually not modified; if so, fdict could be used, since it seems to be faster at creation.

That's an interesting idea. It has always vaguely bothered me that `*args` gives a tuple while `**kwds` gives a dict. Unfortunately it's impossible to change without breaking tons of existing code, since things like `kwds.pop("something")` have become a pretty standard idiom to use it.

And just to be clear for folks that don't know the idiom (it took me a second to remember myself), it's common to do something like:

def spam(**kwargs):
    """Do 'something', then call bacon()."""
    if 'something' in kwargs:

def bacon(**kwargs):

You see this in decorators, for instance, that add an extra argument to do some pre-processing or something before calling the decorated function.