Connecting chrome native messages to a existing in

Question

I have a created a chrome background script and a host using python run by executing a bat file which is linked in the "manifest". Everything kinda works but as far as I understand every time I connect to host with my chrome extension for native messaging I create the python instance and execute the code.

But is it possible to connect to a existing instance(for example I execute a python script) and view the output? I hope my question is understandable.

I also do not understand why when I execute a bat file e get a cmd window but when my chrome background app connect to chrome and data is sent between there is no window. Why this might be like that?