simple question drawing to screen

[Kaminski]

I can't figure out how to draw to screen separately for the LEFT and RIGHT eyes. I just want to make 2-dimensional polygons but have the left and right eyes see completely different views. Heres what I've been trying:

import viz
viz.go(viz.HMD | viz.SEREO)
viz.startlayer(viz.LINE_LOOP)
viz.vertexcolor(viz.BLUE)
viz.linewidth(1)
viz.vertex(0.2,0.2)
viz.vertex(0.2,0.5)
viz.vertex(0.5,0.5)
viz.vertex(0.5,0.2)
line = viz.endlayer(viz.SCREEN,viz.LEFT_EYE)

I know that last line is flat out wrong, but I can't find how to say it.