Future proof total_ordering against changes in methods defined on object.
diff --git a/Lib/functools.py b/Lib/functools.py
index b39e77e..314c0dd 100644
--- a/Lib/functools.py
+++ b/Lib/functools.py
@@ -82,7 +82,7 @@
('__lt__', lambda self, other: not self >= other)]
}
# Find comparisons not inherited from object.
- roots = [op for op in convert if getattr(cls, op) is not getattr(object, op)]
+ roots = [op for op in convert if getattr(cls, op, None) is not getattr(object, op, None)]
if not roots:
raise ValueError('must define at least one ordering operation: < > <= >=')
root = max(roots) # prefer __lt__ to __le__ to __gt__ to __ge__