[Tkinter] AttributeError: 'App' object has no attribute 'set_text'

[Larz60+]

This error no longer matches the code provided in post 1.
Please post the updated code that matches error messages.
when posting errors, please include the full, verbatim, message as it includes valuable information on program flow prior to the error occurrence, and enclose in error tags (highlight code, and click 'circle with X' icon).