First of all, thank you to Chico Venancio for the explanation about "kubectl describe". However it still did not start...

It seems to me that there is a problem with python3.7. When I install the venv for python3.7 (web and base, same problem) and I do a command "hello Kubernetes!", it crashes (deployment file here https://paste.toolforge.org/view/89fc0b13). If I replace 3.7 through 3.5, then It works and returns the hello Kubernetes.

After bringing back everything to Python 3.5, the Celery worker is running (at last!). 

Psemdel