∀ {n : ℕ} {F : TypeVec.{u_1} (n + 1) → Type u_1} [q : MvQPF F] {α β : TypeVec.{u_1} n} (g : α.Arrow β)
  (_a _b : (MvQPF.P F).W α),
  _a ≈ _b → Quot.mk (⇑(MvQPF.wSetoid β)) ((MvQPF.P F).wMap g _a) = Quot.mk (⇑(MvQPF.wSetoid β)) ((MvQPF.P F).wMap g _b)