Is there a way to change the render mode when using run.py?

[spaganowm]

I using run.py to export individual frames from a scene, instead of using the GUI (I have a lot of scenes to process). It exports the "shaded" mode by default, but I'm trying to switch to the "position" mode, to generate a position pass to use in Nuke or After Effects etc.. In the run.py help there is a "--render_mode", but it appears deprecated. I've tried to find where the parameter exists so I can pass my own value, but I can't seem to figure it out. Any help would be appreciated!