diff --git a/Lib/test/test_bool.py b/Lib/test/test_bool.py
index 7da1eabae..fa1131a97 100644
--- a/Lib/test/test_bool.py
+++ b/Lib/test/test_bool.py
@@ -340,6 +340,8 @@ class BoolTest(unittest.TestCase):
         self.assertIs(bool.from_bytes(b'\x00'*8, 'big'), False)
         self.assertIs(bool.from_bytes(b'abcd', 'little'), True)
 
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
     def test_sane_len(self):
         # this test just tests our assumptions about __len__
         # this will start failing if __len__ changes assertions