[ceph-users] 18.2.4 regression: 'diskprediction_local' has failed: No module named 'sklearn'

Upgraded to 18.2.4 yesterday.  Healthy cluster reported a few minutes after the upgrade completed.  Next morning, this: # ceph health detail HEALTH_ERR Module 'diskprediction_local' has failed: No module named 'sklearn' [ERR] MGR_MODULE_ERROR: Module 'diskprediction_local' has failed: No module named 'sklearn'    Module 'diskprediction_local' has failed: No module named 'sklearn' Searching found this was a problem several years ago, then resolved, now returned. Any ideas? Harry Coin