Currently calling ChangesetGet without include_discussion=True will give you dict with 'discussion': [] what is a bit confusing. I (again) got confused why also changesets with some comments also get empty list.

Maybe 'discussion': None would be more clear?

It may break some data consumers but in almost all cases any code that tried to iterate over not actually fetched list of comments was broken anyway.

(I can imagine some exotic case of code distinguishing between empty list and not empty list for changeset known to have comments to detect which version of fetch was performed, but that is at best exotic..)

And big thanks for this library, it is quite useful! And such very minor issues are really rare! I hope feedback like this issue is welcome.