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- Jython support: use ``__builtin__`` module import rather than assuming
``__builtins__`` is available.
- Jython support: deal with the fact that the Jython SAX parser
returns attribute sets that have an empty string indicating no
namespace instead of ``None``.
- Allow ``setup.py test`` to run at least a subset of the tests that
would be run when using the zope testrunner: ``setup.py test`` runs
53 tests, while ``bin/test`` runs 156.