Note that there are a few similar patches posted to gh-4101 and gh-4245.
Those were all patches to msvc9compiler in Python distutils.
Monkeypatching ``MSVCCompiler.link`` is less easy than this change
to ``config._check_compiler``; effect should be the same.

Also updates the error message shown when initializing MSVC fails.

[ci skip]

This private variable has disappeared in later versions of setuptools.
In older versions of setuptools it is the same as
distutils.command.install.install, so use that instead.

Closes #4664.

makes attribute checks more sane and allows adding nonnull

probably irrelevant by now, but emits a warning during compilation.

Run the 2to3 ws_comma fixer on *.py files. Some lines are now too long
and will need to be broken at some point. OTOH, some lines were already
too long and need to be broken at some point. Now seems as good a time
as any to do this with open PRs at a minimum.

Now is as good a time as any with open PR's at a low.

use it

In Python3 `dict.items()`, `dict.keys()`, and `dict.values()` are
iterators. This causes problems when a list is needed so the 2to3 fixer
explicitly constructs a list when is finds on of those functions.
However, that is usually not necessary, so a lot of the work here has
been cleaning up those places where the fix is not needed. The big
exception to that is the `numpy/f2py/crackfortran.py` file. The code
there makes extensive use of loops that modify the contents of the
dictionary being looped through, which raises an error. That together
with the obscurity of the code in that file made it safest to let the
`dict` fixer do its worst.

Closes #3050.