Rename _Py_identifier to _Py_IDENTIFIER.
diff --git a/Objects/setobject.c b/Objects/setobject.c
index 8f6325a..d7990d8 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -1933,7 +1933,7 @@
 set_reduce(PySetObject *so)
 {
     PyObject *keys=NULL, *args=NULL, *result=NULL, *dict=NULL;
-    _Py_identifier(__dict__);
+    _Py_IDENTIFIER(__dict__);
 
     keys = PySequence_List((PyObject *)so);
     if (keys == NULL)