count, PyList_SetItem() does. Very confusing!
must call Py_INCREF() explicitly.
NOTE: functions that 'consume' a reference count like
-PyDict_SetItemString() even
-consume the reference if the object wasn't stored, to simplify error
-handling.
+PyList_SetItemString() even consume the reference if the object wasn't
+stored, to simplify error handling.
It seems attractive to make other functions that take an object as
argument consume a reference count; however this may quickly get