My apologies as this wont have the specifics it should as I’m pressed for time and it was a few days ago when I went through the process so some details are starting to fade.
I started here: Get started with the USB Accelerator | Coral 3 however after getting to the part of installing ‘python3-pycoral’, I later learned that the hosted version of ‘pycoral’ is missing a function(s?)/methods necessary to run the example semantic segmentation script.  It was at that point that the recommended solution was to build from source to get the missing functions/methods and so I tried to build from: “https://github.com/google-coral/pycoral 2” which then led me down a different rabbit hole, where in the end the build failed with errors saying that such-and-such (more than one item) was listed more than once in the build files and thus couldn’t continue.
My question is: Is there a (current) guide anywhere that allows for the Coral TPU example scripts to be ran from a fully updated raspberry Pi 4?
EDIT: The missing module was ‘pycoral.adapters’ which this stackoverflow then recommended building from source: stackoverflow(dot)com/questions/67807906/installing-coral-edge-tpu-software-gives-me-modulenotfounderror-no-module-name  (url butchered because there’s a limit on links)