conversion using the proper magic slot (e.g., __int__()). Also move conversion
code out of PyNumber_*() functions in the C API into the nb_* function.
Applied patch #1109424. Thanks Walter Doewald.
and test_support.run_classtests() into run_unittest()
and use it wherever possible.
Also don't use "from test.test_support import ...", but
"from test import test_support" in a few spots.
From SF patch #662807.
between str, unicode, UserString and the string module
as possible. This increases code coverage in stringobject.c
from 83% to 86% and should help keep the string classes
in sync in the future. From SF patch #662807