UpdateLayer.
sorry I don't quite understand.
In my script I'm creating a temporary data layer, and adding it to my mxd. I then want to make the symbol invisible but turn the labels on. So I need to set the label item, the font, the font size, and the color of the lines to be clear. Does Update Layer do that? The examples seem to be copying over the layer symbology from another existing layer in the mxd. So should I create a dummy layer that has the symbology that just sits in my mxd for the purposes of copying over the symbology definitions?