I just did this. Here is my code:
import arcpy
import os
for dirpath, dirnames, filenames in os.walk(u'R:\Projects\ERI\MXDs\DataDriven'): #Walks through folder containing many different Data Driven MXDs
for filename in filenames:
print filename
basePath = "R:\Projects\ERI\MXDs\DataDriven"
mxd = basePath + "\\" + filename
field_name = "SSN"
mxdFile = arcpy.mapping.MapDocument(mxd)
for i in range(1, mxdFile.dataDrivenPages.pageCount + 1):
mxdFile.dataDrivenPages.currentPageID = i
row = mxdFile.dataDrivenPages.pageRow
outpath = filename.replace(".mxd", "_" + row.getValue(field_name) + ".pdf") #Saves the file based on an attribute within the index layer.
arcpy.mapping.ExportToPDF(mxdFile,r"R:\Projects\ERI\DataDriven_March2016\IndividualPDFs" + "\\" + outpath)