I hope y'all can help me get a handle on using arcpy.mapping. When I run the 4 lines below in the python window, the layers in the project are displayed. But if I uncomment "lyr.visible = False" , nothing happens - I had hoped the layer would be turned off. How would I code turning the layer off?
mxd = arcpy.mapping.MapDocument("CURRENT")
for lyr in arcpy.mapping.ListLayers(mxd):
# lyr.visible = False