Move Doc/tools/sphinxext content to Doc/tools, there is no need for the nested subdirectory anymore.

Issue #18711: Add a new `PyErr_FormatV` function, similar to `PyErr_Format` but accepting a `va_list` argument.

remove delayed calls that were cancelled.

calls that were cancelled.

Remove pointless "vile hack" that can cause the build step to fail when some extension modules can't be imported.

See issue #5309 for the build failures, issue #458343 for the original motivation.

_read_null(), because _read_null() cannot be used on AIX. On AIX, reading from
NULL is allowed: the first page of memory is a mapped read-only on AIX.

_read_null() and _sigabrt() don't accept parameters.

because _read_null() cannot be used on AIX. On AIX, reading from NULL is
allowed: the first page of memory is a mapped read-only on AIX.

crash.

os.posix_fadvise() nor os.posix_fallocate() because their prototypes in system
headers are wrong.

os.posix_fallocate() because their prototypes in system headers are wrong.

-Wsign-compare warnings in unicodeobject.c.  These were all a result
of sizeof() being unsigned and being compared to a Py_ssize_t.
Not actual problems.

From Robert Collins.

cleanup overflowing handling in unicode_decode_call_errorhandler and unicode_encode_ucs1 (closes #22518)

limited by 100.

Patch by Claudiu Popa.