python-pyswarms fails to build with Sphinx 4.0.2 in Fedora 35 (currently Rawhide). + sphinx-build-3 docs html Running Sphinx v4.0.2 making output directory... done Exception occurred: File "/builddir/build/BUILD/pyswarms-1.3.0/docs/conf.py", line 167, in setup app.add_stylesheet("theme_overrides.css") # path relative to static AttributeError: 'Sphinx' object has no attribute 'add_stylesheet' For the logs from testing build attempts, see: https://copr.fedorainfracloud.org/coprs/ksurma/pygments-2.9.0/package/python-pyswarms/ Possible solution to this issue: In some cases it may be enough to replace the call to 'add_stylesheet' with 'add_css_file' instead. You can test you package using Koji scratch build koji build --scratch <srpm> For details regarding the Sphinx change, see https://fedoraproject.org/wiki/Changes/Sphinx4 Let us know here if you have any questions. Thank you!