USB network interface

In order use the USB network interface you need to load the USB gadget kernel module:

sudo modprobe g_ether

Or, if you want to load this module every time you boot:

echo g_ether > /etc/modules-load.d/g_ether.conf

Then, the interface should be visible as usb0.

IO

There is an extensive BeagleBone IO python library from Adafruit.