∀ {α : Type u} {β : Type v} {x : BEq α} {x_1 : Hashable α} {ρ : Type w} [inst : ForIn Id ρ (α × β)]
  {motive : Std.HashMap α β → Prop} (m : Std.HashMap α β) {l : ρ},
  motive m → (∀ (m : Std.HashMap α β) (a : α) (b : β), motive m → motive (m.insert a b)) → motive (m.insertMany l)