based on a suggestion from Tim Peters; also make sure that we're really
doing exponentiation and not multiplication.

bug from compile.c.  (SF bug #456756.)

affect nodes without another operator.  This was causing negated
exponentiations to drop the exponentiation.  This closes SF bug #456756.

tupledealloc(): only feed the free list when the type is really a
tuple, not a subtype.  Otherwise, use PyObject_GC_Del().

_PyTuple_Resize(): disallow using this for tuple subtypes.

PyInt_Check() succeeds.  That returns true for subtypes of int, which
may override __add__ or __sub__.

long_subtype_new(): fix a typo (type->ob_size instead of
tmp->ob_size).

default_getpass().  This should prevent hanging when it is called in
IDLE.

Fixes SF bug #455648.

restricted execution mode.

Algorithm.  This closes SF bug #454917.

"should have" been added here when they were added to lists).

when that test is doomed to deadlock.

If tp_itemsize of the basetype is nonzero, only allow empty __slots__
(declaring that no __dict__ should be added), and don't add a weakref
offset.

visit_finalizer_reachable since it's the same as visit_reachable.
Rename visit_reachable to visit_move.  Objects can now have the GC type
flag set, reachable by tp_traverse and not be in a GC linked list.  This
should make the collector more robust and easier to use by extension
module writers.  Add memory management functions for container objects
(new, del, resize).

the setup script is running from inside Vim.

the old flag to still compile.  Remove the PyType_BASICSIZE and
PyType_SET_BASICSIZE macros.  Add PyObject_GC_New, PyObject_GC_NewVar,
PyObject_GC_Resize, PyObject_GC_Del, PyObject_GC_Track,
PyObject_GC_UnTrack.  Part of SF patch #421893.

the old flag to still compile.