diff --git a/Doc/library/types.rst b/Doc/library/types.rst
index ad40a9f..6f0dc25 100644
--- a/Doc/library/types.rst
+++ b/Doc/library/types.rst
@@ -409,7 +409,9 @@
                return "{}({})".format(type(self).__name__, ", ".join(items))
 
            def __eq__(self, other):
-               return self.__dict__ == other.__dict__
+               if isinstance(self, SimpleNamespace) and isinstance(other, SimpleNamespace):
+                  return self.__dict__ == other.__dict__
+               return NotImplemented
 
    ``SimpleNamespace`` may be useful as a replacement for ``class NS: pass``.
    However, for a structured record type use :func:`~collections.namedtuple`