proposition: Lemma pre_whisker_iso_is_iso {A B C : precategory_data} (F : functor_data A B) {G H : functor_data B C} (gamma : nat_trans G H) (X : is_nat_iso gamma) : is_nat_iso (pre_whisker F gamma).
proof: Proof. intros a. apply X. Defined.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.FunctorCategory