Here is a confession: I am a very strong proponent of a robust test suite being perhaps the single most important asset of a codebase, but when it comes to auxiliary services like admin sites or CLIs when it comes to testing I tend to ask for forgiveness more than I ask for permission. Django's admin site is no different: and, because Django's admin DSL is very magic-string-y, there's a lot of stuff that never gets caught by CI or mypy until a lovely CS agent informs me that something is blow...
