Issue #22423: Unhandled exception in thread no longer causes unhandled
AttributeError when sys.stderr is None.

--HG--
branch : 2.7
Issue #22423: Fixed debugging output of the GROUPREF_EXISTS opcode in the re
module.

--HG--
branch : 2.7
Fixed issue #22415 number in Misc/NEWS for changeset c925b436467a.

--HG--
branch : 2.7