python-enlighten fails to build with Python 3.9.0a4.

ERROR: test_at_exit (tests.test_manager.TestManager)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/builddir/build/BUILD/enlighten-1.4.0/tests/test_manager.py", line 337, in test_at_exit
    manager = _manager.Manager(stream=tty.stdout, counter_class=MockCounter)
  File "/builddir/build/BUILD/enlighten-1.4.0/enlighten/_manager.py", line 73, in __init__
    self.stream = stream or sys.stdout
  File "/usr/lib64/python3.9/unittest/mock.py", line 2146, in __get__
    return self.create_mock()
  File "/usr/lib64/python3.9/unittest/mock.py", line 2142, in create_mock
    _set_return_value(parent, m, entry)
  File "/usr/lib64/python3.9/unittest/mock.py", line 2040, in _set_return_value
    method._mock_wraps = getattr(mock._mock_wraps, name)
AttributeError: '_io.TextIOWrapper' object has no attribute '__bool__'
======================================================================
ERROR: test_direct (tests.test_counter.TestCounter)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/builddir/build/BUILD/enlighten-1.4.0/tests/test_counter.py", line 612, in test_direct
    ctr = Counter(stream=self.tty.stdout, total=100, desc='Test', unit='ticks')
  File "/builddir/build/BUILD/enlighten-1.4.0/enlighten/counter.py", line 30, in __init__
    manager = get_manager(stream=kwargs.get('stream', sys.stdout),
  File "/builddir/build/BUILD/enlighten-1.4.0/enlighten/_manager.py", line 398, in get_manager
    stream = stream or sys.stdout
  File "/usr/lib64/python3.9/unittest/mock.py", line 2146, in __get__
    return self.create_mock()
  File "/usr/lib64/python3.9/unittest/mock.py", line 2142, in create_mock
    _set_return_value(parent, m, entry)
  File "/usr/lib64/python3.9/unittest/mock.py", line 2040, in _set_return_value
    method._mock_wraps = getattr(mock._mock_wraps, name)
AttributeError: '_io.TextIOWrapper' object has no attribute '__bool__'

For the build logs, see:
https://copr-be.cloud.fedoraproject.org/results/@python/python3.9/fedora-rawhide-x86_64/01256082-python-enlighten/

For all our attempts to build python-enlighten with Python 3.9, see:
https://copr.fedorainfracloud.org/coprs/g/python/python3.9/package/python-enlighten/

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 3.9:
https://copr.fedorainfracloud.org/coprs/g/python/python3.9/

Let us know here if you have any questions.

Python 3.9 will be included in Fedora 33. To make that update smoother, we're building Fedora packages with early pre-releases of Python 3.9.
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.