Setting up Dict example puzzled by syntax and functionality

Hi @nilshg and @jling
I hear you both and respect your opinion. I’ll back off from trying to understand what is going on here. One thought about that, I think I might have taken the example out of context so it might be the BEST solution to a problem I didn’t include in my question.

Here is the place I found it. the example I was looking at

thanks for giving me your counsel