Get rid of most of the flags (in tp_flags) that keep track of various
variations of the type struct and its attachments.  In Py3k, all type
structs have to have all fields -- no binary backwards compatibility.
Had to change the complex object to a new-style number!
diff --git a/Modules/_struct.c b/Modules/_struct.c
index 3a44bde..df243ec 100644
--- a/Modules/_struct.c
+++ b/Modules/_struct.c
@@ -1706,7 +1706,7 @@
 	PyObject_GenericGetAttr,	/* tp_getattro */
 	PyObject_GenericSetAttr,	/* tp_setattro */
 	0,					/* tp_as_buffer */
-	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_WEAKREFS,/* tp_flags */
+	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
 	s__doc__,			/* tp_doc */
 	0,					/* tp_traverse */
 	0,					/* tp_clear */