i1 : X = Proj(QQ[x..z]) o1 = X o1 : ProjectiveVariety
i2 : O = OO_X o2 = OO X o2 : SheafOfRings
i3 : variety O o3 = X o3 : ProjectiveVariety
-- ../../../../Macaulay2/m2/varieties.m2:118 variety SheafOfRings := Variety => O -> O.variety