Checking that PYTHONIOENCODING is always "utf8"

I know unittests and use write them daily.

They get executed during development and CI.

Now I have test which I would like to ensure on the production system:

PYTHONIOENCODING must be "utf8"

Above I used the verb "test", this means I want to check the state. This question is not about how to do this.

AFAIK the unittest framework can't help me here, since it only gets executed during development and CI.

How to solve this in the python world withou re-inventing the wheel?

Above is only an example. There are several other things next to PYTHONIOENCODING which I would like to check.

Next use case for these checks: Some days ago we had an issue on the production sever. The command-line tool convert gets used and some versions are broken and create wrong results. I would like to write a simple check to ensure that the convert tool on the production server is not broken.

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