MongoDB - How to remove part of field with $unset

Question

I have a database in MongoDB where there are entries with the following structure image

I am using a script in Python that I use to retrive information from this strucutre and then saves it to a csv.

The end goal is to remove ONLY SOME parts of the parameters structure. For instance, I want to keep parameters[0].values and parameters[1].values but not parameters[2:5].values

I am not experienced in this but the command I am using is the following

{"$unset":"exercises.parameters.values"] }

but this will remove all values from all the objects inside parameters. Since the variable has the same name amongst the objects I can't find a way to specify which ones I want.

I have also tried indexing like so

{"$unset":"exercises.parameters[2].values"] }

but that doesn't seem to work...

Help is much appreciated!