First of all, using print frequently would slow down your Python script.
You could use a lib such as multiprocessing (
https://docs.python.org/3/library/multiprocessing.html) to run the generate_random_wif function in parallel.
This will most likely improve performance, as you will be running multiple instances of the same function at the same time.
With that library, OP probably have to modify his
generate_random_wif function a bit where each process check different possible range/combination.