out the location of the problem. MS_WINDOWS currently implies !HAVE_WCSFTIME,
so the addition of !defined(HAVE_WCSFTIME) is for readability.

I added some tests in 2105ab8553b7 and found no bug, but it turns out
that the doctest is not actually run.  While converting the doctest to
unittest style, I stumbled upon this bug again and this time applied the
code patch provided by Filip Gruszczyński.

Issue #13521: dict.setdefault() now does only one lookup for the given key, making it "atomic" for many purposes.
Patch by Filip Gruszczyński.

Issue #13521: dict.setdefault() now does only one lookup for the given key, making it "atomic" for many purposes.
Patch by Filip Gruszczyński.

Issue #14123: Explicitly mention that old style % string formatting has caveats but is not going away any time soon.

but is not going away any time soon.

#14081: The sep and maxsplit parameter to str.split, bytes.split, and bytearray.split may now be passed as keyword arguments.

When people find bugs in scripts such as reindent.py, msgfmt.py or
pygettext.py, we have to try to reproduce the bug manually, apply a fix
and test manually again.  The alternative is to only read the code and
trust that it works.  This test file is a way to stop that
unsatisfactory state of things and write proper unit tests instead.