The getEuler() command return a list with yaw, pitch, and roll. You can get the individual values directly:
Code:
yaw,pitch,roll = vizconnect.getTracker('HeadTracker').getEuler()
Or first save the list and then get the individual values:
Code:
ori = vizconnect.getTracker('HeadTracker').getEuler()
yaw = ori[0]
pitch = ori[1]
roll = ori[2]