How to Replace Smart Layer Text with a Script

[wangxshuai]

Here I have a psd file, i want to replace the text in the smart layer

I have completed half of the script with the help of other issus and documents

import photoshop.api as ps
App = ps.Application()
doc = App.load('*.psd')

a = App.stringIDToTypeID("placeLayerEditContents")
b = ps.ActionDscriptor()
App.executeAction(a,b)

now I open the smart object, but i have no idea to change the text in the opened smart object, how to seleted the opened smart object layer,? And how to change the text in the opened smart object layer ?