switch back to prior version and fixed tag to be class level attribute.
switch back to prior version and fixed tag to be class level attribute.

weidnem/IntroPython2016,weidnem/IntroPython2016,UWPCE-PythonCert/IntroPython2016,Baumelbi/IntroPython2016,UWPCE-PythonCert/IntroPython2016,Baumelbi/IntroPython2016,UWPCE-PythonCert/IntroPython2016,weidnem/IntroPython2016