> from xml.etree.ElementTree import _namespace_map
>
> And the import in cElementTree won't be necessary.
> After all, _namespace_map is definitely not a public API!

Because of the interaction of the support.import_fresh_module with the CleanContext context manager, it's not so easy to remove black magic.
I don't find better than:

        if hasattr(ET, '_namespace_map'):
            _namespace_map = ET._namespace_map
        else:
            from xml.etree.ElementTree import _namespace_map


This is why I kept the import in the deprecated "cElementTree" at first.
It does not hurt (it's private API), and it makes the test easier.

( If you have doubts, try ./python -m test test_xml_etree{,_c} or variants. )


I will probably commit code and documentation at once. It makes things easier regarding traceability.