Attached is a verifier for the binary code used by the _sre module (this
is often called bytecode, though to distinguish it from Python bytecode
I put it in quotes).

I wrote this for Google App Engine, and am making the patch available as
open source under the Apache 2 license.  Below are the copyright
statement and license, for completeness.

Barry, I'm assigning this to you only so that you can decide whether
this is okay to check in before beta3.  The patch works for 2.6 as well
as for 3.0 (and even for 2.5, but I don't think it's worth changing that
-- or is it?).  If you agree (which I hope you will do), please assign
back to me with instructions and I'll submit it.  The performance impact
is minimal: it only runs when the compiled "bytecode" is passed from the
re compiler (written in Python) to the C code, during the sre
compilation stage.  All tests pass.  We've had this code in use in App
Engine since April without complaints.

# Copyright 2008 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

It's not necessary to include these copyrights and bytecode in the
source file.  Google has signed a contributor's agreement with the PSF
already.