`(@IsIsomorphism C x y p) `(q : morphism C x z) `(r : morphism C y z) : r = (q o p^-1) -> (r o p) = q. Proof. iso_concat_t. Qed.
Require Import Category.Core Functor.Core. Require Import HoTT.Tactics Basics.Trunc Basics.Tactics Types.Sigma Equivalences.