In my case, starting about a week ago I installed tensorflow directly, then keras from conda, and was ok until I installed bazel today, which updated some things that broke tensorflow, so I just updated dask, whatever that is, and that fixed tensorflow, but bazel looks cryptic to configure, so I'm running with unoptimized tensorflow on a mac laptop to keep my room warm.
Epoch 4/10
1664/2038 [=======================>......] - ETA: 1551s - loss: 0.5030