py3compile fails on error output

line 331 of py3compile fails when there is output from the child process as sys.stderr.write expects a string, but process.communicate returns a byte array:

328 (child_output, child_unused) = process.communicate()
329 if process.returncode not in (None, 0):
330 # FIXME: find out the package the file belongs to
331 sys.stderr.write(child_output)
332 rv = process.returncode

this aborts py3compile on stderr output.
example is in bug 730144 where an invalid syntax causes stderr output:

Setting up python3-cxx (6.2.0-4build1) ...
Traceback (most recent call last):
  File "/usr/bin/py3compile", line 336, in <module>
    main()
  File "/usr/bin/py3compile", line 331, in main
    sys.stderr.write(child_output)
TypeError: must be str, not bytes

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: python3 3.2~rc1-2
ProcVersionSignature: Ubuntu 2.6.38-6.34-generic 2.6.38-rc7
Uname: Linux 2.6.38-6-generic x86_64
Architecture: amd64
Date: Mon Mar 14 17:59:34 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Alpha amd64 (20110301.6)
ProcEnviron:
 LANGUAGE=en_US:en
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: python3-defaults
UpgradeStatus: No upgrade log present (probably fresh install)