∀ {α : Type u} [inst : BEq α] [inst_1 : Hashable α] {β : Type v} [EquivBEq α] [LawfulHashable α] [inst_4 : Inhabited α]
  {l : List (α × β)} {k : α},
  (List.map Prod.fst l).contains k = false →
    (↑(Std.DHashMap.Internal.Raw₀.Const.insertMany Std.DHashMap.Internal.Raw₀.emptyWithCapacity l)).getKey! k = default