Issue #16991: Add a C implementation of collections.OrderedDict.
diff --git a/Objects/object.c b/Objects/object.c
index c1d7a05..be12be5 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -1607,6 +1607,21 @@
     if (PyType_Ready(&PyDict_Type) < 0)
         Py_FatalError("Can't initialize dict type");
 
+    if (PyType_Ready(&PyODict_Type) < 0)
+        Py_FatalError("Can't initialize OrderedDict type");
+
+    if (PyType_Ready(&PyODictKeys_Type) < 0)
+        Py_FatalError("Can't initialize odict_keys type");
+
+    if (PyType_Ready(&PyODictItems_Type) < 0)
+        Py_FatalError("Can't initialize odict_items type");
+
+    if (PyType_Ready(&PyODictValues_Type) < 0)
+        Py_FatalError("Can't initialize odict_values type");
+
+    if (PyType_Ready(&PyODictIter_Type) < 0)
+        Py_FatalError("Can't initialize odict_keyiterator type");
+
     if (PyType_Ready(&PySet_Type) < 0)
         Py_FatalError("Can't initialize set type");