What is the proper way to access the active scene in a driver expression?

Question

I tried to access the FPS setting of the render settings in a shader node through a driver expression. The attempt was successful, but I got a warning and a tip saying:

WARNING: Driver expression may not work correctly

TIP: bpy.context is not safe for renderfarm usage

According to this thread the proper way to set the active scene is through bpy.context. Therefor, I assumed, that the proper way to get the active scene would be through bpy.context as well. This warning however makes me feel like there is a more proper way to access scene data (like render settings) through drivers so they would also work in renderfarms.

So my question is: How do I properly access this kind of data in a driver expression?

You'll have to modify the drivers namespace because the expression field can't directly acces the context See How can a blender driver python script access scene properties like FPS? — Gorgious, Feb 15 '21 at 22:07
@Gorgious thanks, that helps a lot! Seems like I was using too abstract search terms. Probably would have found that if I literally looked for my specific problem. — narranoid, Feb 16 '21 at 13:41
You can simply enter the word frame into expression, and it will refer to the current frame. To slow down, you can do, frame * 0.01 — Noob Cat, Feb 21 '21 at 12:59

What is the proper way to access the active scene in a driver expression?

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