fact: Definition abses_directsum_distributive_pullbacks `{Univalence} {A B B' C D D' : AbGroup@{u}} {E : AbSES B A} {F : AbSES D C} (f : B' $-> B) (g : D' $-> D) : abses_pullback (functor_ab_biprod f g) (abses_direct_sum E F) = abses_direct_sum (abses_pullback f E) (abses_pullback g F) := (abses_pullback_component1_id (abses_directsum_pullback_morphism f g) (fun _ => idpath))^.
imports: Basics Types HSet Limits.Pullback WildCat Pointed.Core Homotopy.ExactSequence Modalities.ReflectiveSubuniverse AbGroups.AbelianGroup AbGroups.AbPullback AbGroups.Biproduct AbSES.Core AbSES.DirectSum