∀ {α : Type u_1} (l : Batteries.RBNode α) (v : α) (r' l' a : Batteries.RBNode α) (y : α) (b : Batteries.RBNode α),
  r' = (Batteries.RBNode.node Batteries.RBColor.black a y b).reverse →
    (∀ (a : Batteries.RBNode α) (x : α) (b : Batteries.RBNode α),
        r' = Batteries.RBNode.node Batteries.RBColor.black a x b → False) →
      (l.balance2 v (Batteries.RBNode.node Batteries.RBColor.red a y b)).reverse =
        Batteries.RBNode.node Batteries.RBColor.red r' v l'