fact: Definition three_disp_ob_mor : disp_cat_ob_mor (arrow C).
imports: UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Prelude UniMath.CategoryTheory.PrecategoryBinProduct UniMath.CategoryTheory.DisplayedCats.Core UniMath.CategoryTheory.DisplayedCats.Total UniMath.CategoryTheory.Limits.Graphs.Colimits UniMath.CategoryTheory.DisplayedCats.Examples.Arrow