fact: Definition IsInitialMorphism_property_morphism_property (M : IsInitialMorphism Ap) (Y : D) (f : morphism C X (U Y)) : (U _1 (IsInitialMorphism_property_morphism M Y f)) o IsInitialMorphism_morphism M = f := concat (CommaCategory.p (@center _ (M (CommaCategory.Build_object !X U tt Y f)))) (right_identity _ _ _ _).
imports: Category.Core Functor.Core Category.Dual Functor.Dual Category.Objects InitialTerminalCategory.Core InitialTerminalCategory.Functors Trunc Types.Sigma HoTT.Tactics Basics.Tactics