Issue #1683: prevent forking from interfering in threading storage.

Issue #3863: Disabled a unit test of fork being called from a thread
when running on platforms known to exhibit OS bugs when attempting that.

in struct's L format.

Decimal.max_mag and Decimal.min_mag.

propagating exceptions.

context manager's __exit__ method's result while it's being converted to bool.

Backport of r67266

Backport r66804: #1415508 from Rocky Bernstein: add docstrings for enable_interspersed_args(), disable_interspersed_args()

and then remove it. Written by Guilherme Polo (gpolo). Backport of r67082.

does not return an iterator for the 4th and 5th items.
(sequence-like and mapping-like state)

Backport of r67049.

snv rev 59943 and 59946.

module.

garbage collection of a Profiler object.

For example:
   "".count("xxxx", sys.maxint, 0)

Backport of r66631.

Reviewed by Fredrik Lundh and Skip Montanaro.

Backport from trunk.

 - Issue #3678: Correctly pass LDFLAGS and LDLAST to the linker on shared
   library targets in the Makefile.

Reviewed by Benjamin Peterson.