lensfun-tools includes the lensfun-update-data command. This uses the lensfun python module, which is provided by the python3-lensfun package. python3-lensfun currently isn't required by lensfun-tools, so if you install lensfun-tools and run lensfun-update-data, it fails. Adding a lensfun-tools dependency on python3-lensfun would fix this issue.
Confirmed, thanks. Fix on the way... http://pkgs.fedoraproject.org/cgit/rpms/lensfun.git/commit/?id=bd7af31fadc3852cba2324e0297b7450ab1c3322
lensfun-0.3.2-7.fc25 has been submitted as an update to Fedora 25. https://bodhi.fedoraproject.org/updates/FEDORA-2017-a3018ee07a
lensfun-0.3.2-7.fc24 has been submitted as an update to Fedora 24. https://bodhi.fedoraproject.org/updates/FEDORA-2017-ff76e0527d
lensfun-0.3.2-7.fc24 has been pushed to the Fedora 24 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-ff76e0527d
lensfun-0.3.2-7.fc25 has been pushed to the Fedora 25 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-a3018ee07a
lensfun-0.3.2-7.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.
lensfun-0.3.2-7.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.