Definition ContentsMap_II_FUN
           (NB2':block)
            (b:block):
            ZMap.t memval.

Lemma ContentsMap_II_existsT: forall (NB2':block) , { M : PMap.t (ZMap.t memval) | fst M = ZMap.init Undef /\ forall b, PMap.get b M = ContentsMap_II_FUN NB2' b}.