(O1 O2 : Subuniverse) `{O1 <= O2} {A B : Type} (f : A -> B) `{MapIn O1 A B f} : MapIn O2 f. Proof. intros b; rapply (inO_leq O1 O2). Defined.
Require Import HoTT.Basics HoTT.Types. Require Import Equiv.BiInv Extensions HProp HFiber NullHomotopy Limits.Pullback. Require Import Homotopy.IdentitySystems. Require Import Colimits.Pushout.