fact: Definition ap_prod_l_path_universe A {B C} (f : B <~> C) : equiv_path (A * B) (A * C) (ap (prod A) (path_universe f)) = equiv_functor_prod_l f.
imports: HoTT.Basics Types.Sigma Types.Forall Types.Arrow Types.Paths Types.Equiv Types.Bool Types.Prod