ung via I2C =====
Raspberry Pi GPIOs mittels I2C Port Expander erweitern
[[https://tutorials-raspberrypi.de/gpios-mittels-i2c-port-expander-erweitern/]]
[[http://www.elektronx.de/... ====
[[https://www.mikrocontroller.net/articles/Port-Expander_PCF8574]]
===== Tasten =====
==== Ma... en lock does not work, install xscreensaver)
#
import os #for OS program calls
import sys #For Clean sy
