fact: Definition cat_prod_corec {z : A} : (z $-> x) -> (z $-> y) -> (z $-> cat_prod x y).
imports: Basics EquivGpd Types.Prod WildCat.Core WildCat.ZeroGroupoid WildCat.Equiv WildCat.Yoneda WildCat.Universe WildCat.NatTrans WildCat.Opposite