I have to stand corrected. noahm@ wrote me, because the Debian Cloud Image maintainer only ever included python explicitly in Azure images. The most likely explanation for the change in the Google images is that Google just ported the last parts of their own software to python 3, and subsequently removed python 2.

With some relieve one can just conclude it's only our own fault that we did not build our own images, which include all our own dependencies. Take it as reminder to always build your own images. Always. Be it VMs or docker. Build your own image.

Original Post

Fun in the morning, we realized that the Debian Cloud image builds dropped python 2 and that propagated to the Google provided Debian/buster images. So in case you use something like ansible, and so far assumed python 2 as the default interpreter, and installed additional python 2 modules to support ansible modules, you now have to either install python 2 again or just move to python 3k.

We just try to suffer it through now, and set interpreter_python = auto in our ansible.cfg to anticipate the new default behaviour, which is planned for ansible 2.12. See also https://docs.ansible.com/ansible/latest/reference_appendices/interpreter_discovery.html

Other lesson to learn here: The GCE Debian stable images are not stable. Blends in nicely with this rant, though it's not 100% a Google Cloud foul this time.