commit fb8899a597c5ef39706215a894fc8c5f5dbf85bc
author Raymond Hettinger <python@rcn.com> Mon May 26 00:40:09 2014 -0700
committer Raymond Hettinger <python@rcn.com> Mon May 26 00:40:09 2014 -0700
tree 01ef4ab677dc3fb8edb3a2c36202f21ca27ff0a7
parent f643b9a9c79928c4ca28d895e7e9a1dcf827cf00

Issue #21481:  Teach argparse equality tests to return NotImplemented when comparing to unknown types.

Lib/argparse.py

diff --git a/Lib/argparse.py b/Lib/argparse.py
index a4009d0..b5bb19a 100644
--- a/Lib/argparse.py
+++ b/Lib/argparse.py
@@ -1157,9 +1157,13 @@
     __hash__ = None
 
     def __eq__(self, other):
+        if not isinstance(other, Namespace):
+            return NotImplemented
         return vars(self) == vars(other)
 
     def __ne__(self, other):
+        if not isinstance(other, Namespace):
+            return NotImplemented
         return not (self == other)
 
     def __contains__(self, key):