diff --git a/Modules/_ctypes/ctypes.h b/Modules/_ctypes/ctypes.h
index b21fe92..12b56c4 100644
--- a/Modules/_ctypes/ctypes.h
+++ b/Modules/_ctypes/ctypes.h
@@ -108,7 +108,7 @@
     ffi_type *atypes[1];
 } CThunkObject;
 extern PyTypeObject PyCThunk_Type;
-#define CThunk_CheckExact(v)        ((v)->ob_type == &PyCThunk_Type)
+#define CThunk_CheckExact(v)        (Py_TYPE(v) == &PyCThunk_Type)
 
 typedef struct {
     /* First part identical to tagCDataObject */
diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
index 929616f..b52402f 100644
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -1661,8 +1661,8 @@
 };
 
 statichere PyTypeObject Element_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "Element", sizeof(ElementObject), 0,
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "Element", sizeof(ElementObject), 0,
     /* methods */
     (destructor)element_dealloc, /* tp_dealloc */
     0, /* tp_print */
@@ -2031,8 +2031,8 @@
 }
 
 statichere PyTypeObject TreeBuilder_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "TreeBuilder", sizeof(TreeBuilderObject), 0,
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "TreeBuilder", sizeof(TreeBuilderObject), 0,
     /* methods */
     (destructor)treebuilder_dealloc, /* tp_dealloc */
     0, /* tp_print */
@@ -2897,8 +2897,8 @@
 }
 
 statichere PyTypeObject XMLParser_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "XMLParser", sizeof(XMLParserObject), 0,
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "XMLParser", sizeof(XMLParserObject), 0,
     /* methods */
     (destructor)xmlparser_dealloc, /* tp_dealloc */
     0, /* tp_print */
diff --git a/Modules/_json.c b/Modules/_json.c
index be1e079..39ec467 100644
--- a/Modules/_json.c
+++ b/Modules/_json.c
@@ -1767,8 +1767,7 @@
 
 static
 PyTypeObject PyScannerType = {
-    PyObject_HEAD_INIT(NULL)
-    0,                    /* tp_internal */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "_json.Scanner",       /* tp_name */
     sizeof(PyScannerObject), /* tp_basicsize */
     0,                    /* tp_itemsize */
@@ -2344,8 +2343,7 @@
 
 static
 PyTypeObject PyEncoderType = {
-    PyObject_HEAD_INIT(NULL)
-    0,                    /* tp_internal */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "_json.Encoder",       /* tp_name */
     sizeof(PyEncoderObject), /* tp_basicsize */
     0,                    /* tp_itemsize */
diff --git a/Modules/_lsprof.c b/Modules/_lsprof.c
index 049c94d..6090c7d 100644
--- a/Modules/_lsprof.c
+++ b/Modules/_lsprof.c
@@ -817,8 +817,7 @@
 ");
 
 statichere PyTypeObject PyProfiler_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0,                                      /* ob_size */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "_lsprof.Profiler",                     /* tp_name */
     sizeof(ProfilerObject),                 /* tp_basicsize */
     0,                                      /* tp_itemsize */
diff --git a/Modules/_sqlite/connection.c b/Modules/_sqlite/connection.c
index 237d6e4..439542e 100644
--- a/Modules/_sqlite/connection.c
+++ b/Modules/_sqlite/connection.c
@@ -293,7 +293,7 @@
     Py_XDECREF(self->statements);
     Py_XDECREF(self->cursors);
 
-    self->ob_type->tp_free((PyObject*)self);
+    Py_TYPE(self)->tp_free((PyObject*)self);
 }
 
 /*
diff --git a/Modules/_sqlite/cursor.c b/Modules/_sqlite/cursor.c
index db36004..ad607d9 100644
--- a/Modules/_sqlite/cursor.c
+++ b/Modules/_sqlite/cursor.c
@@ -135,7 +135,7 @@
         PyObject_ClearWeakRefs((PyObject*)self);
     }
 
-    self->ob_type->tp_free((PyObject*)self);
+    Py_TYPE(self)->tp_free((PyObject*)self);
 }
 
 PyObject* _pysqlite_get_converter(PyObject* key)
diff --git a/Modules/_sre.c b/Modules/_sre.c
index 6fd3aff..94b3d50 100644
--- a/Modules/_sre.c
+++ b/Modules/_sre.c
@@ -2712,8 +2712,8 @@
 };
 
 statichere PyTypeObject Pattern_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "_" SRE_MODULE ".SRE_Pattern",
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "_" SRE_MODULE ".SRE_Pattern",
     sizeof(PatternObject), sizeof(SRE_CODE),
     (destructor)pattern_dealloc, /*tp_dealloc*/
     0,                                  /* tp_print */
@@ -3952,8 +3952,8 @@
 };
 
 statichere PyTypeObject Scanner_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0, "_" SRE_MODULE ".SRE_Scanner",
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "_" SRE_MODULE ".SRE_Scanner",
     sizeof(ScannerObject), 0,
     (destructor)scanner_dealloc, /*tp_dealloc*/
     0,				/* tp_print */
diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index ecc473c..7691b51 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -187,8 +187,7 @@
  *   PyType_Ready if it hasn't already been called
  */
 static PyTypeObject _HashInheritanceTester_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0,                          /* Number of items for varobject */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "hashinheritancetester",            /* Name of this type */
     sizeof(PyObject),           /* Basic object size */
     0,                          /* Item size for varobject */
@@ -315,8 +314,7 @@
 };
 
 static PyTypeObject _MemoryViewTester_Type = {
-    PyObject_HEAD_INIT(NULL)
-    0,                          /* Number of items for varobject */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "memoryviewtester",         /* Name of this type */
     sizeof(PyObject),           /* Basic object size */
     0,                          /* Item size for varobject */
diff --git a/Modules/arraymodule.c b/Modules/arraymodule.c
index f6f597a..5bd3a42 100644
--- a/Modules/arraymodule.c
+++ b/Modules/arraymodule.c
@@ -1292,9 +1292,9 @@
         PyErr_SetString(PyExc_TypeError, "arg must be open file");
         return NULL;
     }
-    if (self->ob_size > 0) {
+    if (Py_SIZE(self) > 0) {
         if (fwrite(self->ob_item, self->ob_descr->itemsize,
-                   self->ob_size, fp) != (size_t)self->ob_size) {
+                   Py_SIZE(self), fp) != (size_t)Py_SIZE(self)) {
             PyErr_SetFromErrno(PyExc_IOError);
             clearerr(fp);
             return NULL;
@@ -1348,7 +1348,7 @@
             if ((*self->ob_descr->setitem)(self,
                             Py_SIZE(self) - n + i, v) != 0) {
                 Py_SIZE(self) -= n;
-                if (itemsize && (self->ob_size > PY_SSIZE_T_MAX / itemsize)) {
+                if (itemsize && (Py_SIZE(self) > PY_SSIZE_T_MAX / itemsize)) {
                     return PyErr_NoMemory();
                 }
                 PyMem_RESIZE(item, char,
@@ -1444,7 +1444,7 @@
 static PyObject *
 array_tostring(arrayobject *self, PyObject *unused)
 {
-    if (self->ob_size <= PY_SSIZE_T_MAX / self->ob_descr->itemsize) {
+    if (Py_SIZE(self) <= PY_SSIZE_T_MAX / self->ob_descr->itemsize) {
         return PyString_FromStringAndSize(self->ob_item,
                             Py_SIZE(self) * self->ob_descr->itemsize);
     } else {
@@ -2289,8 +2289,8 @@
 {
     PyObject *m;
 
-    Arraytype.ob_type = &PyType_Type;
-    PyArrayIter_Type.ob_type = &PyType_Type;
+    Py_TYPE(&Arraytype) = &PyType_Type;
+    Py_TYPE(&PyArrayIter_Type) = &PyType_Type;
     m = Py_InitModule3("array", a_methods, module_doc);
     if (m == NULL)
         return;
diff --git a/Modules/datetimemodule.c b/Modules/datetimemodule.c
index 4573637..34b8ed4 100644
--- a/Modules/datetimemodule.c
+++ b/Modules/datetimemodule.c
@@ -3039,8 +3039,7 @@
 PyDoc_STR("Abstract base class for time zone info objects.");
 
 statichere PyTypeObject PyDateTime_TZInfoType = {
-    PyObject_HEAD_INIT(NULL)
-    0,                                          /* ob_size */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "datetime.tzinfo",                          /* tp_name */
     sizeof(PyDateTime_TZInfo),                  /* tp_basicsize */
     0,                                          /* tp_itemsize */
@@ -3564,8 +3563,7 @@
 };
 
 statichere PyTypeObject PyDateTime_TimeType = {
-    PyObject_HEAD_INIT(NULL)
-    0,                                          /* ob_size */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "datetime.time",                            /* tp_name */
     sizeof(PyDateTime_Time),                    /* tp_basicsize */
     0,                                          /* tp_itemsize */
@@ -4692,8 +4690,7 @@
 };
 
 statichere PyTypeObject PyDateTime_DateTimeType = {
-    PyObject_HEAD_INIT(NULL)
-    0,                                          /* ob_size */
+    PyVarObject_HEAD_INIT(NULL, 0)
     "datetime.datetime",                        /* tp_name */
     sizeof(PyDateTime_DateTime),                /* tp_basicsize */
     0,                                          /* tp_itemsize */