GoPiGo distence sensor

[ldompeling at casema.nl]

I have a small robot on wheels named the GoPiGo.
What I want is if the distence sensor read the same distence for let say 5 seconds then the GoPiGo go's backward.

But I don't now how to program this in python.
The Api functions for the GoPiGo are here: http://www.dexterindustries.com/GoPiGo/programming/python-programming-for-the-raspberry-pi-gopigo/

Can someone help me with this.