{X : AlgebraicGeometry.Scheme} →
  (I : X.IdealSheafData) →
    (U : ↑X.affineOpens) →
      ↑(I.glueDataObj U).toPresheafedSpace ≅
        { carrier := ↑(X.zeroLocus ↑(I.ideal U) ∩ ↑↑U), str := instTopologicalSpaceSubtype }