∀ {X Y : AlgebraicGeometry.Scheme} (f : X ⟶ Y),
  CategoryTheory.CategoryStruct.comp
      (AlgebraicGeometry.Scheme.Modules.pullbackComp (CategoryTheory.CategoryStruct.id X) f).inv
      (CategoryTheory.CategoryStruct.comp
        ((AlgebraicGeometry.Scheme.Modules.pullback f).whiskerLeft (AlgebraicGeometry.Scheme.Modules.pullbackId X).hom)
        (AlgebraicGeometry.Scheme.Modules.pullback f).rightUnitor.hom) =
    CategoryTheory.eqToHom ⋯