proposition: Lemma nat_trans_fix_fst_arg_ax: is_nat_trans _ _ nat_trans_fix_fst_arg_data.
proof: Proof. red. intros d d' f. unfold nat_trans_fix_fst_arg_data, functor_fix_fst_arg; simpl. unfold functor_fix_fst_arg_mor; simpl. assert (nat_trans_ax_inst := nat_trans_ax α). apply nat_trans_ax_inst. Qed.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.FunctorCategory UniMath.CategoryTheory.opp_precat