proposition: Lemma postcompWithCoproductArrow {a b : C} (CCab : CoproductCocone a b) {c : C} (f : a --> c) (g : b --> c) {x : C} (k : c --> x) : CoproductArrow CCab f g · k = CoproductArrow CCab (f · k) (g · k).
proof: Proof. apply CoproductArrowUnique. - rewrite assoc, CoproductIn1Commutes; apply idpath. - rewrite assoc, CoproductIn2Commutes; apply idpath. Qed.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.CategoryTheory.FunctorCategory UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Limits.Graphs.Colimits UniMath.CategoryTheory.RepresentableFunctors.Representation