Restart compositing from script?

[ttzn (T NZ)]

I have a rendering problem which I wanted to solve by writing a script:

High resolution panoramic images (with multiple cameras and view layers)

Hi, I would like to ask for advice rendering an apartment. I have cameras in each room, all room is arranged into separate view layers. These cameras are also set up as panorama cameras. I would like to render each room into a high resolution panoramic image and apply compositing on each image too. I think I managed to figure out the compositing. I created a render layer node for each view layer and directed them into their own final composite node. So far this part is working. The bigger que…

So I wrote a script which splits up my scene into N chunks and renders those borders into EXRs. Use compositing is turned off at this point. After that the script generates compositing node group to join everything back to one image so I can apply my own compositing. (If I do compositing on the chunks the merged result will have borders around the chunks of course)

In the nodes I simply use CompositorNodeImage to load the generated EXRs and the output of the group will route to my compositing nodes and that routes to a normal file output with an output PNG.

The question is how to force blender to re-run this newly generated compositing setup?