fact: Definition is_retract {x y x' y' : C} (f : x --> y) (f' : x' --> y') (ix : x' --> x) (rx : x --> x') (iy : y' --> y) (ry : y --> y') : UU := (ix · rx = identity x') × (iy · ry = identity y') × (ix · f = f' · iy) × (rx · f' = f · ry).
imports: UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Prelude UniMath.CategoryTheory.opp_precat