The following failure is showing up frequently in the buildbots.  I haven't checked closely enough to be sure if it is a heisenberg, but I suspect it is, since it doesn't seem to be related to any of the recent changesets that would have been included in the builds that just failed and that show the failure:

======================================================================
FAIL: test_warnings (test.test_logging.WarningsTest)
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Traceback (most recent call last):
  File "/usr/home/db3l/buildarea/3.3.bolen-freebsd/build/Lib/test/test_logging.py", line 1796, in test_warnings
    "dummy.py:42: UserWarning: Explicit\n  Dummy line\n")
AssertionError: '\nWarning (from warnings module):\n  File "dummy.py", line 42\n    Dummy line\n [truncated]... != 'dummy.py:42: UserWarning: Explicit\n  Dummy line\n'
+ dummy.py:42: UserWarning: Explicit
- 
- Warning (from warnings module):
-   File "dummy.py", line 42
-     Dummy line
? --
+   Dummy line
- UserWarning: Explicit
- >>>