∀ {α : Type u} {β : α → Type v} {m : Std.DHashMap.Raw α β} [inst : BEq α] [inst_1 : Hashable α] [EquivBEq α]
  [LawfulHashable α],
  m.WF →
    ∀ {k : α} {v : β k},
      (m.insert k v).toList.Perm (⟨k, v⟩ :: List.filter (fun x => decide ¬(k == x.fst) = true) m.toList)