python-zope-testrunner fails to build with Python 3.10.0b1:

Failure in test /builddir/build/BUILD/zope.testrunner-5.3.0/lib/python3.10/site-packages/zope/testrunner/tests/testrunner-debugging-import-failure.rst
Failed doctest test for testrunner-debugging-import-failure.rst
  File "/builddir/build/BUILD/zope.testrunner-5.3.0/lib/python3.10/site-packages/zope/testrunner/tests/testrunner-debugging-import-failure.rst", line 0
----------------------------------------------------------------------
File "/builddir/build/BUILD/zope.testrunner-5.3.0/lib/python3.10/site-packages/zope/testrunner/tests/testrunner-debugging-import-failure.rst", line 36, in testrunner-debugging-import-failure.rst
Failed example:
    try:
        zope.testrunner.run_internal(['--path', dir, '-D'])
    except zope.testrunner.interfaces.EndRun: print('EndRun raised')
    finally: sys.stdin = real_stdin
    # doctest: +ELLIPSIS +REPORT_NDIFF
Differences (ndiff with -expected +actual):
    -   File ".../TESTS-DIR/tests.py", line 2
    ?         ^^^
    +   File "/tmp/tmp4ig17sak/TESTS-DIR/tests.py", line 2
    ?         ^^^^^^^^^^^^^^^^
          impot doctest
    -                 ^
    - SyntaxError: invalid syntax
    - > ...find.py(NNN)import_name()
    +     ^
    + SyntaxError: invalid syntax. Perhaps you forgot a comma?
    + <BLANKLINE>
    + > /builddir/build/BUILD/zope.testrunner-5.3.0/lib/python3.10/site-packages/zope/testrunner/find.py(NNN)import_name()
      -> __import__(name)
      (Pdb) c
      EndRun raised

...snip many more like this...

See this entire section about this change in Python 3.10:
https://docs.python.org/3.10/whatsnew/3.10.html#better-error-messages


For the build logs, see:
https://copr-be.cloud.fedoraproject.org/results/@python/python3.10/fedora-rawhide-x86_64/02172772-python-zope-testrunner/

For all our attempts to build python-zope-testrunner with Python 3.10, see:
https://copr.fedorainfracloud.org/coprs/g/python/python3.10/package/python-zope-testrunner/

Testing and mass rebuild of packages is happening in copr. You can follow these instructions to test locally in mock if your package builds with Python 3.10:
https://copr.fedorainfracloud.org/coprs/g/python/python3.10/

Let us know here if you have any questions.

Python 3.10 will be included in Fedora 35. To make that update smoother, we're building Fedora packages with early pre-releases of Python 3.10.
A build failure prevents us from testing all dependent packages (transitive [Build]Requires), so if this package is required a lot, it's important for us to get it fixed soon.
We'd appreciate help from the people who know this package best, but if you don't want to work on this now, let us know so we can try to work around it on our side.