apply QPF.M.bisim (λ x y => corec (bind.automaton k) (.inr x) = y)
F : Type u → Type u
inst : QPF F
R S : Type u
k : R → Free F S
⊢ ∀ (x y : Free F S), corec (bind.automaton k) (Sum.inr x) = y → x = y
F : Type u → Type u
inst : QPF F
R S : Type u
k : R → Free F S
⊢ ∀ (x y : QPF.M (FreeF F S)),
    corec (bind.automaton k) (Sum.inr x) = y →
      QPF.M.liftr (FreeF F S) (fun x y => corec (bind.automaton k) (Sum.inr x) = y) (QPF.M.destruct x)
        (QPF.M.destruct y)