Genshi doesn't support Python 3.8

[hodgestar]

It's the usual AST changes that break Genshi on every Python release.

From the original Genshi tracker bug report https://genshi.edgewall.org/ticket/612:

Python 3.8 now uses ast.Constant type and remove types like _ast.Str: ast.Str is a backward compatibility class.

I had to disable Genshi benchmark in the performance project: ​python/pyperformance#46

Example of issue: "strarg = _new(_ast.Str, node.id)" at genshi/template/eval.py:616: the code should use ast.Str, not _ast.Str.

See also https://bugs.python.org/issue32892.

Update: And the Python 3.8 release schedule -- https://www.python.org/dev/peps/pep-0569/ (release currently scheduled for 20 October 2019).

[FelixSchwarz]

I assume nobody came up with a patch so far? (Fedora is preparing a Python 3.8 upgrade and unsurprisingly Genshi fails to build.)

downstream issue is Fedora bug 1693485: "python-genshi FTBFS with Python3.8"

[hroncok]

I have a fix ready. Running tox to see if I broke something. I'm afraid I no longer have Python 2.5 around.

[hroncok]

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