code: def registerDeletionUpgrader(itemType, fromVersion, toVersion):
      
      # XXX This should actually do something more special so that a new table is
      # not created and such.
      def upgrader(old):
          old.deleteFromStore()
          return None
      registerUpgrader(upgrader, itemType.typeName, fromVersion, toVersion)
docs: Register an upgrader for C{itemType}, from C{fromVersion} to C{toVersion},
      which will delete the item from the database.
  
      @param itemType: L{axiom.item.Item} subclass
      @return: None