In my opinion, this property shouldn't have a setter. Instead there should be a method `add_visualization_frame`. I think ideally there would also be a method `remove_visualization_frame`, but that makes it all a little bit more complex, and may not be necessary.

I also discourage the use of the `vframe` abbreviation in the actual code, unless we rename `VisualizationFrame` to `VFrame`. I personally prefer the long names.