∀ {X Y Z : AlgebraicGeometry.Scheme} (𝒰 : X.OpenCover) (f : X ⟶ Z) (g : Y ⟶ Z)
  [inst : ∀ (i : 𝒰.I₀), CategoryTheory.Limits.HasPullback (CategoryTheory.CategoryStruct.comp (𝒰.f i) f) g]
  (i j : 𝒰.I₀),
  CategoryTheory.Limits.HasPullback ((AlgebraicGeometry.Scheme.Pullback.gluing 𝒰 f g).ι j)
    (CategoryTheory.Limits.pullback.fst (AlgebraicGeometry.Scheme.Pullback.p1 𝒰 f g) (𝒰.f i))