fact: Definition nat_trans_to_core : F₁ ⟹ F₂.
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.Groupoids UniMath.CategoryTheory.opp_precat UniMath.CategoryTheory.PrecategoryBinProduct