Proposition make_is_left_lifting {h : z --> y} (τ : f ==> h · g) (F : ∏ (k : z --> y) (θ : f ==> k · g), h ==> k) (HF₁ : ∏ (k : z --> y) (θ : h ==> k), F k (τ • (θ ▹ g)) = θ) (HF₂ : ∏ (k : z --> y) (θ : f ==> k · g), τ • (F k θ ▹ g) = θ) : is_left_lifting τ. Proof. intros k. use isweq_iso. - exact (F k). - exact (HF₁ k). - exact (HF₂ k). Defined.
Require Import UniMath.Foundations.All. Require Import UniMath.MoreFoundations.All. Require Import UniMath.CategoryTheory.Core.Prelude. Require Import UniMath.Bicategories.Core.Bicat. Import Bicat.Notations. Require Import UniMath.Bicategories.Core.Examples.OpMorBicat. Require Import UniMath.Bicategories.Core.Examples.OpCellBicat.