make sure the builtin help function doesn't fail when sys.stdin is not a valid file (closes #11709)
Original patch by Amaury Forgeot d'Arc with a test by bdettmer.
diff --git a/Misc/NEWS b/Misc/NEWS
index 155811e..e3827bb 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -28,6 +28,9 @@
- Issue #21304: Backport the key derivation function hashlib.pbkdf2_hmac from
Python 3 per PEP 466.
+- Issue #11709: Fix the pydoc.help function to not fail when sys.stdin is not a
+ valid file.
+
- Issue #13223: Fix pydoc.writedoc so that the HTML documentation for methods
that use 'self' in the example code is generated correctly.