diff --git a/Include/setobject.h b/Include/setobject.h
index 6a829f0..b6849e1 100644
--- a/Include/setobject.h
+++ b/Include/setobject.h
@@ -74,6 +74,15 @@
 	  PyType_IsSubtype((ob)->ob_type, &PySet_Type) || \
 	  PyType_IsSubtype((ob)->ob_type, &PyFrozenSet_Type))
 
+PyAPI_FUNC(PyObject *) PySet_New(PyObject *);
+PyAPI_FUNC(PyObject *) PyFrozenSet_New(PyObject *);
+PyAPI_FUNC(int) PySet_Size(PyObject *anyset);
+#define PySet_GET_SIZE(so) (((PySetObject *)(so))->used)
+PyAPI_FUNC(int) PySet_Contains(PyObject *anyset, PyObject *key);
+PyAPI_FUNC(int) PySet_Discard(PyObject *anyset, PyObject *key);
+PyAPI_FUNC(int) PySet_Add(PyObject *set, PyObject *key);
+PyAPI_FUNC(PyObject *) PySet_Pop(PyObject *set);
+
 #ifdef __cplusplus
 }
 #endif