∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] [inst_1 : CategoryTheory.Limits.HasTerminal C]
  [inst_2 : CategoryTheory.Limits.HasPullbacks C] (X Y : C) [inst_3 : CategoryTheory.Limits.HasBinaryProduct X Y],
  CategoryTheory.CategoryStruct.comp (prodIsoPullback X Y).hom
      (CategoryTheory.Limits.pullback.snd (CategoryTheory.Limits.terminal.from X)
        (CategoryTheory.Limits.terminal.from Y)) =
    CategoryTheory.Limits.prod.snd