Proposal: add/remove method in pydantic/dataclasses for multivalued fields

[cmungall]

LinkML follows idiomatic python in having no java beans/POJO style getters/setters.

There is potentially an argument for generating these for multivalued fields. See https://stackoverflow.com/questions/75508779/how-do-i-add-a-class-to-a-schemadefinition-in-linkml

This might be particularly handy for adding to collections that are inlined as dict, which currently require a mildly repetitive

obj=MyCls('ID123', ...)
container.objs[obj.id]=obj

Alternatively, there could be an option for having separate builder-style objects.