Linking model and class labels?

I’m about to implement a simple model-label-wrapper that outputs a classification probability vector in the form of a dictionary with class labels as keys (rather than a ‘dictionary’ indexed by integers). Semantically, the label set is a part of the model, IMO, so they should be linked together at the lowest possible code level.

Is there a standard way of bundling a classification model with its label set?

I use .json file to do it. I don’t know any other way of solving it sorry.