Fix typo in constant name.
diff --git a/Objects/listobject.c b/Objects/listobject.c
index 7c63acf..c1cacaf 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -672,7 +672,7 @@
 		return (PyObject *)self;
 	}
 
-	if (size > Py_SSIZE_T_MAX / n) {
+	if (size > PY_SSIZE_T_MAX / n) {
 		return PyErr_NoMemory();
 	}