∀ {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]
  {Z : C} (h : X ⟶ Z),
  CategoryTheory.CategoryStruct.comp (prodIsoPullback X Y).inv
      (CategoryTheory.CategoryStruct.comp CategoryTheory.Limits.prod.fst h) =
    CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Limits.pullback.fst (CategoryTheory.Limits.terminal.from X)
        (CategoryTheory.Limits.terminal.from Y))
      h