ioc-writer fails to build with Python 3.10.0a2.

ERROR: ioc_writer (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: ioc_writer
Traceback (most recent call last):
  File "/usr/lib64/python3.10/unittest/loader.py", line 470, in _find_test_path
    package = self._get_module_from_name(name)
  File "/usr/lib64/python3.10/unittest/loader.py", line 377, in _get_module_from_name
    __import__(name)
  File "/builddir/build/BUILD/ioc_writer-0.3.3/ioc_writer/__init__.py", line 1, in <module>
    from ioc_writer import ioc_api
  File "/builddir/build/BUILD/ioc_writer-0.3.3/ioc_writer/ioc_api.py", line 25, in <module>
    from lxml import etree as et
ImportError: /usr/lib64/python3.10/site-packages/lxml/etree.cpython-310-x86_64-linux-gnu.so: undefined symbol: _PyGen_Send


======================================================================
ERROR: tests (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: tests
Traceback (most recent call last):
  File "/usr/lib64/python3.10/unittest/loader.py", line 154, in loadTestsFromName
    module = __import__(module_name)
  File "/builddir/build/BUILD/ioc_writer-0.3.3/tests/tests.py", line 18, in <module>
    from lxml import etree as et
ImportError: /usr/lib64/python3.10/site-packages/lxml/etree.cpython-310-x86_64-linux-gnu.so: undefined symbol: _PyGen_Send


======================================================================
ERROR: tests.tests (unittest.loader._FailedTest)
----------------------------------------------------------------------
ImportError: Failed to import test module: tests.tests
Traceback (most recent call last):
  File "/usr/lib64/python3.10/unittest/loader.py", line 436, in _find_test_path
    module = self._get_module_from_name(name)
  File "/usr/lib64/python3.10/unittest/loader.py", line 377, in _get_module_from_name
    __import__(name)
  File "/builddir/build/BUILD/ioc_writer-0.3.3/tests/tests.py", line 18, in <module>
    from lxml import etree as et
ImportError: /usr/lib64/python3.10/site-packages/lxml/etree.cpython-310-x86_64-linux-gnu.so: undefined symbol: _PyGen_Send
 
This seem to be related to https://github.com/cython/cython/issues/3876. 
It might be fixed with this patch https://github.com/cython/cython/pull/3877 that works for numpy. Upstream has decided to solve this differently, but until that happens, we are using this patch in our Copr (for other packages).

For the build logs, see:
https://copr-be.cloud.fedoraproject.org/results/@python/python3.10/fedora-rawhide-x86_64/01757092-ioc-writer/

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

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.