exportImportRenderGlobalsJson

from maya import cmds
import maya.app.renderSetup.model.renderSetup as renderSetup

def exportFile(filename):
    with open(filename, "w+") as file:
        json.dump(renderSetup.instance().encode(None), fp=file, indent=2, sort_keys=True)
        
exportFile(filename)       



import json

filename = "/home/mark/maya/Presets/temp.json"

def importRenderSetup(pFilename):
    with open(pFilename, "r") as file:
        renderSetup.instance().decode(json.load(file), renderSetup.DECODE_AND_OVERWRITE, None)

importRenderSetup(filename)