Save this in a file with extension ".py"

import poser
scene = poser.Scene()

EXCLUDEDACTORS="UNIVERSE","GROUND",

for ac in scene.Actors() :
    if ac.InternalName() in EXCLUDEDACTORS : continue
    if (ac.IsProp() or ac.IsBodyPart()):
        print ac.Name()
        for mat in ac.Materials() :
            n=mat.ShaderTree().Node(0)
            n.InputByInternalName("Ambient_Color").SetColor(0,0,0)
            n.InputByInternalName("Ambient_Value").SetFloat(0)
        
scene.DrawAll()
print "Done."

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