The version of python-testtools in EPEL is really, really old. Please build a more current version.
FEDORA-EPEL-2020-2983db6387 has been submitted as an update to Fedora EPEL 7. https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2020-2983db6387
FEDORA-EPEL-2020-2983db6387 has been pushed to the Fedora EPEL 7 testing repository.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-EPEL-2020-2983db6387
See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.
FEDORA-EPEL-2020-2983db6387 has been pushed to the Fedora EPEL 7 stable repository.
If problem still persists, please make note of it in this bug report.