∀ {α : Type u} [inst : AddGroup α] [inst_1 : SizeOf α] (toTopologicalSpace : TopologicalSpace α)
  (toIsTopologicalAddGroup : IsTopologicalAddGroup α),
  sizeOf { toTopologicalSpace := toTopologicalSpace, toIsTopologicalAddGroup := toIsTopologicalAddGroup } =
    1 + sizeOf toTopologicalSpace + sizeOf toIsTopologicalAddGroup