[docs] [issue17589] Make documentation about macros in C API explicit about rvalue vs statement

Georg Brandl added the comment: There are also some macros usable as lvalues, such as Py_REFCNT or Py_SIZE (they aren't documented at all currently). Anyway, documenting as statement-only unless explicitly stated differently is fine with me. ---------- _______________________________________ Python tracker <report@bugs.python.org> <http://bugs.python.org/issue17589> _______________________________________