docs: def set_default(*params):
      """
      INPUT dicts IN PRIORITY ORDER
      UPDATES FIRST dict WITH THE MERGE RESULT, WHERE MERGE RESULT IS DEFINED AS:
      FOR EACH LEAF, RETURN THE HIGHEST PRIORITY LEAF VALUE
      """
      p0 = params[0]
      agg = p0 if p0 or _get(p0, CLASS) in data_types else {}
      for p in params[1:]:
          p = unwrap(p)
          if p is None:
              continue
          _all_default(agg, p, seen={})
      return wrap(agg)