Exclude top and right lines from a plot frame

Hi,

Is there some convenient way to setup a frame in axes which only has the bottom and left lines?

I've tried some workaround solution like this:
a = subplot(211)
a.set_frame_on(False)
a.hlines(ymin,xmin,xmax)
a.vlines(xmin,ymin,ymax)

Is there a more appropriate solution?

thanks,
Dejan