∀ {σ : Type u_1} {A : Type u} [inst : CommRing A] [inst_1 : SetLike σ A] [inst_2 : AddSubgroupClass σ A] (𝒜 : ℕ → σ)
  [inst_3 : GradedRing 𝒜] {X : AlgebraicGeometry.Scheme} (f : A →+* ↑(X.presheaf.obj (Opposite.op ⊤)))
  (hf : Ideal.map f (HomogeneousIdeal.irrelevant 𝒜).toIdeal = ⊤),
  AlgebraicGeometry.Proj.openCoverOfMapIrrelevantEqTop 𝒜 f hf =
    X.openCoverOfIsOpenCover (fun ir => X.basicOpen (f ir.snd.fst)) ⋯