PEP 3123: Provide forward compatibility with Python 3.0, while keeping
backwards compatibility. Add Py_Refcnt, Py_Type, Py_Size, and
PyVarObject_HEAD_INIT.
diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
index f21cf56..d8a28b4 100644
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -269,7 +269,7 @@
 
 staticforward PyTypeObject Element_Type;
 
-#define Element_CheckExact(op) ((op)->ob_type == &Element_Type)
+#define Element_CheckExact(op) (Py_Type(op) == &Element_Type)
 
 /* -------------------------------------------------------------------- */
 /* element constructor and destructor */
@@ -1207,7 +1207,7 @@
         /* FIXME: support arbitrary sequences? */
         PyErr_Format(
             PyExc_TypeError,
-            "expected list, not \"%.200s\"", item->ob_type->tp_name
+            "expected list, not \"%.200s\"", Py_Type(item)->tp_name
             );
         return -1;
     }
@@ -1440,7 +1440,7 @@
 
 staticforward PyTypeObject TreeBuilder_Type;
 
-#define TreeBuilder_CheckExact(op) ((op)->ob_type == &TreeBuilder_Type)
+#define TreeBuilder_CheckExact(op) (Py_Type(op) == &TreeBuilder_Type)
 
 /* -------------------------------------------------------------------- */
 /* constructor and destructor */
@@ -1607,7 +1607,7 @@
         Py_INCREF(data); self->data = data;
     } else {
         /* more than one item; use a list to collect items */
-        if (PyString_CheckExact(self->data) && self->data->ob_refcnt == 1 &&
+        if (PyString_CheckExact(self->data) && Py_Refcnt(self->data) == 1 &&
             PyString_CheckExact(data) && PyString_GET_SIZE(data) == 1) {
             /* expat often generates single character data sections; handle
                the most common case by resizing the existing string... */
@@ -2623,9 +2623,9 @@
 #endif
 
     /* Patch object type */
-    Element_Type.ob_type = TreeBuilder_Type.ob_type = &PyType_Type;
+    Py_Type(&Element_Type) = Py_Type(&TreeBuilder_Type) = &PyType_Type;
 #if defined(USE_EXPAT)
-    XMLParser_Type.ob_type = &PyType_Type;
+    Py_Type(&XMLParser_Type) = &PyType_Type;
 #endif
 
     m = Py_InitModule("_elementtree", _functions);