proposition: Proposition identity_hor_comp_laws {C : category} {D : twosided_disp_cat C C} (Cm : hor_comp D) : double_functor_hor_comp_laws (identity_hor_comp_data Cm).
proof: Proof. intros x₁ x₂ y₁ y₂ z₁ z₂ v₁ v₂ v₃ h₁ h₂ k₁ k₂ s₁ s₂ ; cbn. rewrite id_two_disp_left, id_two_disp_right. rewrite transport_b_b_disp_mor2. use transportb_disp_mor2_eq. apply idpath. Qed.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.TwoSidedDisplayedCats.TwoSidedDispCat UniMath.CategoryTheory.TwoSidedDisplayedCats.Isos UniMath.CategoryTheory.TwoSidedDisplayedCats.DisplayedFunctor UniMath.Bicategories.DoubleCategories.Basics.DoubleCategoryBasics