fact: Definition natequiv_inverse {A B : Type} `{IsGraph A} `{HasEquivs B} {F G : A -> B} `{!Is0Functor F, !Is0Functor G} : NatEquiv F G -> NatEquiv G F.
imports: Basics.Overture Basics.Tactics WildCat.Core WildCat.Equiv WildCat.Square