Issue #13889: On MSVC builds, set FPU control word at runtime for all string <-> float conversions.  Patch by Samuel Iseli and Stefan Krah.

_socket does.  Some were using the older wsock32.lib.

PEP 328 in explaining how 'index' works.

__import__('mod', {'__packaging__': 'pkg', level=1) w/o properly (and
thus not segfaulting).

Python 3.3 thanks to importlib finishing the work in PEP 328 that
accidently got carried forward.

importlib._bootstrap is now frozen into Python/importlib.h and stored
as _frozen_importlib in sys.modules. Py_Initialize() loads the frozen
code along with sys and imp and then uses _frozen_importlib._install()
to set builtins.__import__() w/ _frozen_importlib.__import__().

Only use a single #ifdef for the 3 functions.

attributes.