fact: Definition to_O_natural {A B : Type} (f : A -> B) : (O_functor f) o (to O A) == (to O B) o f := (O_rec_beta _).
imports: HoTT.Basics HoTT.Types Equiv.BiInv Extensions HProp HFiber NullHomotopy Limits.Pullback PathAny Colimits.Pushout