One of the biggest issues with Python (our preferred development language) is dependency management.  Any individual deployment can result in minor differences in the versions of the files and libraries which make up the application.  And these minor variations introduce uncertainty and randomness into our deployment process. So, we've investigated…

Through the use of the Poetry project, incremental changes, and a little luck, the Django 1.11 -> 2.2 and django CMS 3.4 -> 3.7 upgrade was a success, but not without some excessively harsh profanity.