[Python-3000] PEP 3123: Making PyObject_HEAD conform to standard C (Was: Dropping PyObject_HEAD)

["Martin v. Löwis"]

> An example of how this will change current code would be good.  E.g.,
> ``o->ob_type->tp_name`` becomes ``PyType(o)->typ_name`` or
> ``o->ob_base->ob_type->tp_name``.
> 
> Otherwise I am all for cleaning up the codebase and thus support this PEP.

Thanks for the suggestions, I have add them all into PEP 3123.

I also changed the PEP title, to reflect that PyObject_HEAD is
maintained for compatibility.

Regards,
Martin