Using one child class method in another child class

[garynewport]

Thank you and, yes, I was confusing the names (which I should not have done).

And again, yes, I am seriously out of practice in the use of classes, etc. Mix that with trying to learn matplotlib, tkinter, customtkinter (originally tried Qt5 and Qt6), whilst doing other things alongside and, I am certainly confused (both linguistically and in their application).

I am reading around this but also using things like your help gives me something to work with.

Again, thank you; and I am seriously grateful.