Need help using BASIC with Impress

I am just getting started with LibreOffice and wanted to know how i can modify a text box’s content? I can’t seem to find any attribute as the textbox’s ID or name using which I can access it.

There is some code at Automatically change the font of all text boxes in Impress and getDrawPage fails in Impress document. If you are not able to get it to work, then edit the question to show example code that you have tried so far.