List Shape/Mesh Relatives for Selected Objects and Render Pass Primary Visibility

listSelShapeRelatives.py

#Creats a list of all selected objects name of shape/mesh node

import maya.cmds as cmds

cmds.listRelatives(cmds.ls(selection=True), type='mesh')

renderLayerPrimaryVis.py

#Changes primary visibility for the currently selected objects on the current render layer
import maya.cmds as cmds

for shape in cmds.listRelatives(cmds.ls(selection=True), type='mesh'):
    cmds.setAttr('%s.primaryVisibility' % shape, 0)