bpo-30470: Deprecate invalid ctypes call protection on Windows.

[Mariatta]

Calling Ctypes functions is deprecated in 3.6.2 and will be removed in 3.7

[mention-bot]

@Mariatta, thanks for your PR! By analyzing the history of the files in this pull request, we identified @birkenfeld, @benjaminp and @theller to be potential reviewers.

[Mariatta]

@zooba @Haypo or @ned-deily can one of you review please? I'm not sure if I'm doing this right. Thanks :)

[Syeberman]

This comment suggests that ctypes functions cannot be called, i.e. that the GetModuleHandleA() call in the next paragraph will soon be unsupported.

Perhaps move this deprecation warning down below the "ctypes tries to protect you from calling functions with the wrong number of arguments" paragraph (line 164/170) and reword as "This protection against incorrect arguments is deprecated and will be removed."

[zooba]

Agreed. I'd get really specific here with something like "Calling ctypes functions with incorrect arguments, either number or type, is unsupported and may no longer raise a ValueError."

It might even make more sense to insert the note directly above the paragraph below that says "ctypes tries to protect you...". Or just remove that section and add a note saying "ctypes may raise a ValueError after calling the function if it detects that an invalid number of arguments were passed. This behavior is deprecated, should not be relied upon, and will be removed in Python 3.7"

[Mariatta]

Thanks @Syeberman and @zooba. I made the change as you suggested. Please check.
I'll resolve the conflict once you're ok with this change.

[Mariatta]

Resolved the conflict

[Syeberman]

LGTM