trying to 'grab' information ( data ) from a computer usb and using it in a programe ( python )
You can and should use your computer to obtain USB traffic to a device, however you should first to overcome your misconceptions about USB. To begin, you need to study some introductory materials like this one, 

You will learn that you can't communicate over USB just by writing some ports in a computer language. The USB uses highly sophisticated and complex serial interface that implements "pipes" instead of plain registers/ports. To get the pipes running, one needs to construct complex data structures in main memory, a whole linked list of them, and instruct USB controller to run the list. This is a pretty complicated layer, which is normally hidden in system host driver and in a driver that gets loaded upon discovery of connected USB device. Applications communicate with USB device drivers via system messages and other OS-defined system mechanisms. 

if you really want to try, here are specifications for the most used host controller EHCI.