fact: Definition abses_path_pullback_projection_commsq {A B B' : AbGroup@{u}} (bt : B' $-> B) (E : AbSES B A) (F : AbSES B' A) (p : abses_pullback bt E = F) : exists phi : middle F $-> E, projection E o phi == bt o projection F.
imports: Basics Types HSet Limits.Pullback WildCat Pointed.Core Homotopy.ExactSequence Modalities.ReflectiveSubuniverse AbGroups.AbelianGroup AbGroups.AbPullback AbGroups.Biproduct AbSES.Core AbSES.DirectSum