Show or hide ArcMap map document (.mxd) map grids using comtypes and ArcObjects

mxd_map_grid_show_hide.py

'''
This code shows how to hide/show map grids in a map document before exporting the map. 
This can be handy when you have multiple grids with different grid cell size and you 
want to be able to control at what map scales each of the map grids should be visible.
As this is not exposed via arcpy, you have to use ArcObjects.
This code assumes there are two grids for the data frame with the name `small` and `large`
'''

import sys
from comtypes.client import GetModule, CreateObject
import arcpy
import arcpy.mapping as mp
from snippets102 import GetStandaloneModules, InitStandalone
esriCarto = GetModule(r"C:\Program Files (x86)\ArcGIS\Desktop10.4\com\esriCarto.olb")
# Running this code for the first time, you would need to import
#the “StandaloneModules”. Can comment out later.
GetStandaloneModules()
InitStandalone()

mxd_path = r'C:\GIS\arcobjects\MapGridMXD.mxd'

#----------------------------------------------------------------------
def export_map(show_scale):
    handle_grids(show_scale)

    mxd = mp.MapDocument(mxd_path)
    df = arcpy.mapping.ListDataFrames(mxd,"Layers")[0]
    lyr = arcpy.mapping.ListLayers(df,'states')[0]

    if show_scale == 'large':
        arcpy.SelectLayerByAttribute_management(lyr,'NEW_SELECTION',
                                                '''STATE_NAME = 'California' ''')

    df.zoomToSelectedFeatures()
    arcpy.mapping.ExportToPNG(mxd,r'C:\GIS\out_{}.png'.format(show_scale),"PAGE_LAYOUT")

#----------------------------------------------------------------------
def handle_grids(show_scale):
    #creating a map document object
    mxdObject = CreateObject(esriCarto.MapDocument, interface=esriCarto.IMapDocument)
    mxdObject.Open(mxd_path)

    #accessing the map
    IMap = mxdObject.ActiveView.FocusMap

    activeView = mxdObject.ActiveView
    pageLayout = activeView.QueryInterface(esriCarto.IPageLayout)
    graphicsContainer = pageLayout.QueryInterface(esriCarto.IGraphicsContainer)

    #IFrameElement
    frameElement = graphicsContainer.FindFrame(IMap)

    #IMapFrame
    mapFrame = frameElement.QueryInterface(esriCarto.IMapFrame)

    #IMapGrids
    mapGrids = mapFrame.QueryInterface(esriCarto.IMapGrids)
    [mapGrids.MapGrid(i) for i in xrange(mapGrids.MapGridCount)]

    grids = [mapGrids.MapGrid(i) for i in xrange(mapGrids.MapGridCount)]

    for g in grids:
        print g.Name
        if show_scale.lower() in g.Name.lower():
            g.Visible = True
        else:
            g.Visible = False

    for g in grids:
        print g.Name, g.Visible

    #or perhaps better to create copies
    mxdObject.Save()

export_map('large')
export_map('small')