Solved! Go to Solution.
import arcpy mxd = arcpy.mapping.MapDocument(r"C:\Project\Project.mxd") df = arcpy.mapping.ListDataFrames(mxd, "Census")[0] lyr = arcpy.mapping.ListLayers(mxd, "StatePopulation", df)[0] lyrFile = arcpy.mapping.Layer(r"C:\Project\LYRs\Population.lyr") arcpy.mapping.UpdateLayer(df, lyr, lyrFile, True) if lyr.symbologyType == "GRADUATED_SYMBOLS": lyr.symbology.valueField = "POP2000" lyr.symbology.classBreakValues = [250000, 999999, 4999999, 9999999, 35000000] lyr.symbology.classBreakLabels = ["250,000 to 999,999", "1,000,000 to 4,999,999", "5,000,000 to 9,999,999", "10,000,000 to 35,000,000"] arcpy.mapping.ExportToPDF(mxd, r"C:\Project\Output\StatePopulation.pdf") del mxd, lyrFile