diff --git a/poky/meta/lib/oe/classextend.py b/poky/meta/lib/oe/classextend.py
index 662707b..e25122e 100644
--- a/poky/meta/lib/oe/classextend.py
+++ b/poky/meta/lib/oe/classextend.py
@@ -1,3 +1,7 @@
+#
+# SPDX-License-Identifier: GPL-2.0-only
+#
+
 import collections
 
 class ClassExtender(object):