Code review comment for lp:~takluyver/unattended-upgrades/py3

Also, test_against_real_archive fails for me even in unchanged trunk:

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FAIL: test_against_real_archive (__main__.TestAgainstRealArchive)
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Traceback (most recent call last):
  File "./test_against_real_archive.py", line 47, in test_against_real_archive
    self.assertFalse(" ERROR " in log)
AssertionError: True is not false

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Ran 1 test in 9.248s