what is ,*, ?

[Skaperen]

This '*' specifies an argument that can be supplied only by keyword.

keyword-only: specifies an argument that can be supplied only by keyword. Keyword-only parameters can be defined by including a single var-positional parameter or bare * in the parameter list of the function definition before them, for example kw_only1 and kw_only2 in the following:

def func(arg, *, kw_only1, kw_only2): ...

 

so, where ,*, is not used, the documentation is saying that these arguments, or those before the ,*,, can be provided by either a named option or be unnamed in the position shown?

so, is this how to code a function prototype to do that?

def f(positional, either_way_with_default_value='foo', *, only_as_a_named_option='bar'): ...

???

so how can a definition of an argument specifying that it can be given either way define the difference between a required argument and one that is not required (e.g. calling f() above with just one positional  argument)?