fact: Variable G'' : Functor D C.
imports: Category.Core Functor.Core NaturalTransformation.Core Functor.Identity Functor.Composition.Core NaturalTransformation.Composition.Core NaturalTransformation.Composition.Laws NaturalTransformation.Identity NaturalTransformation.Paths Functor.Dual NaturalTransformation.Dual Adjoint.Core Adjoint.UnitCounit Adjoint.Dual Adjoint.Functorial.Parts HoTT.Tactics Basics.Tactics