diff --git a/Lib/test/test_descrtut.py b/Lib/test/test_descrtut.py
index 514e398..8088819 100644
--- a/Lib/test/test_descrtut.py
+++ b/Lib/test/test_descrtut.py
@@ -208,6 +208,7 @@
      '__setattr__',
      '__setitem__',
      '__setslice__',
+     '__sizeof__',
      '__str__',
      '__subclasshook__',
      'append',