reindent _cursesmodule.c
reindent _cursesmodule.c

Use untabify.py + emacs (python3 mode) + manual editions for
Py_BEGIN_ALLOW_THREADS / Py_END_ALLOW_THREADS

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator