∀ (C : Type u) [inst : CategoryTheory.Category.{v, u} C] [inst_1 : HomotopicalAlgebra.CategoryWithFibrations C]
  {X Y Z : C} (f : X ⟶ Z) (g : Y ⟶ Z) [inst_2 : CategoryTheory.Limits.HasPullback f g]
  [(HomotopicalAlgebra.fibrations C).IsStableUnderBaseChange] [hf : HomotopicalAlgebra.Fibration f],
  HomotopicalAlgebra.Fibration (CategoryTheory.Limits.pullback.snd f g)