fact: Definition filler_comm {x y a b : C} {f : x --> y} {g : a --> b} {h : x --> a} {k : y --> b} {H : h · g = f · k} (l : filler H) := pr2 l.
imports: UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Prelude UniMath.CategoryTheory.opp_precat UniMath.CategoryTheory.Limits.Opp UniMath.ModelCategories.Retract UniMath.ModelCategories.MorphismClass UniMath.CategoryTheory.DisplayedCats.Examples.Arrow