mxd.dataDrivenPages.pageRow.setValue() doesn't work

[Dazzling]

I'd like to write a Python script to help me deal with making illustrations that are filtered by some number in each layer, and then I want DataDrivenPages to zoom into the corresponding view. However, I have encountered an error as follows:

I have checked the document about 'pageRow', and I knew it was read-only, but it could then be read and/or modified as necessary. But I don't know why this code cannot work.

This is the code:

import arcpy
import arcpy.mapping as mapping
import xlrd

work_book = xlrd.open_workbook(r'C:\Users\39470\Desktop\schedule.xls')
size = work_book.sheets()[0].nrows
kqbh, kqmc = [], []
for i in range(1, size):
    kqmc.append(work_book.sheets()[0].row(i)[2].value)
    kqbh.append(work_book.sheets()[0].row(i)[3].value)
mxd = mapping.MapDocument('CURRENT')
layers = mapping.ListLayers(mxd)
for number, name in zip(kqbh, kqmc):
    if number != '':
        mxd.dataDrivenPages.pageRow.setValue('KQBH', number)
        for lyr in layers:
            if lyr.isFeatureLayer:
                if lyr.symbologyType == 'UNIQUE_VALUES':
                    sym = lyr.symbology
                    df = mapping.ListDataFrames(mxd)[0]
                    sym.valueField = 'KQBH'
                    sym.classValues = [number]
                    sym.classLabels = [lyr.name]
                    sym.showOtherValues = False
                    arcpy.RefreshActiveView()
                    arcpy.RefreshTOC()
    mxd.saveACopy(r'C:\Users\39470\Desktop\illustrations\\' + name + '.mxd')

Can anyone help me?

Thanks!