skaringa

I found the solution [here](https://stackoverflow.com/questions/65366442/cannot-convert-a-symbolic-keras-input-output-to-a-numpy-array-typeerror-when-usi) Solved this by adding the statements ``` from tensorflow.python.framework.ops import disable_eager_execution disable_eager_execution() ``` at the beginning of the notebook.

There is a related discussion/ticket at https://sourceforge.net/p/raspberry-gpio-python/tickets/210/ It seems that especially for event detection the RPi.GPIO library is outdated.