This bug is part of the non-responsive maintainer procedure for brouhaha, following https://docs.fedoraproject.org/en-US/fesco/Policy_for_nonresponsive_package_maintainers/. Please respond if you are still active in Fedora and want to maintain python-cattrs.
cattrs upstream doesn't yet support Python 3.8. I'm not going to hack it myself. If you aren't willing to wait for upstream Python 3.8 support, feel free to take whatever action you think is appropriate.
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