Objects in-memory exchange between modules

Development
1

Greeting!

I’m developing a few scripted modules for plant MRI data processing and lifecycle management, two of which act as clients for a remote FastAPI server. The modules have different purposes; therefore, they are kept separate, but the authorization is the same in each module, and I have to authorize twice every time when a user opens two modules.
My question is: how to pass information in-memory between modules - is there some Slicer object/singleton with global accessibility? I guess the scope of view of the parameter node is within the module only; I need a “global parameter node”.
I also want to avoid exchanging information in temporary files and look for an in-memory object. At first, I’d like to store authorization tokens there, but not limited to, in the future. Can you suggest if there is such a place in Slicer?

2

I don’t quite understand. Are you using more Slicer instances? If not, then the “global parameter node” is the MRML scene, where you can keep anything, like a text node or a scripted module node for storing scene-wide information.