The packages are stuck on py3.6 which means they will be pain once we switch to 3.7. Please test them on 3.7 *and* 3.8 (so we don't to revisit this in a few months), and update PYTHON_COMPAT appropriately. If it doesn't work, please either fix it, remove Python or issue last rites. Please consider this urgent.
Fixed in commit aa56a04f.
Cleanup of py27/py36-only 1.9.0 unfortunately depends on exaile 4.1.0 version bump.