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 */