With Python officially unsupported upstream and vendors only providing important security fixes for it we need to migrate completely to Python3 ASAP.

The core code base is mostly ported in terms of the backends and facilities related to hosting general research data.

We're testing and weeding out any remaining issues on development systems and a few smaller production sites.
Any issues related to the original complete grid compute stack should be gradually tested and handled in the separate milestone for that part specifically.