∀ {α : Type u_1} {β : Type u_2} (f : α → β) (g : β → α) (s : Set α) (t : Set β) (ml : ∀ ⦃x : α⦄, x ∈ s → f x ∈ t)
  (mr : ∀ ⦃x : β⦄, x ∈ t → g x ∈ s) (il : ∀ ⦃x : α⦄, x ∈ s → g (f x) = x) (ir : ∀ ⦃x : β⦄, x ∈ t → f (g x) = x),
  ↑{ toFun := f, invFun := g, source := s, target := t, map_source' := ml, map_target' := mr, left_inv' := il,
          right_inv' := ir }.symm =
    g