code: def close(self):
          "Close the shelve object, which is needed for data consistency."
          if self.is_open:
              logger.info('closing shelve data')
              try:
                  self.shelve.close()
                  self._shelve.clear()
              except Exception:
                  self.is_open = Falsf close(self):
          "Close the shelve object, which is needed for data consistency."
          if self.is_open:
              logger.info('closing shelve data')
              try:
                  self.shelve.close()
                  self._shelve.clear()
              except Exception:
                  self.is_open = False
docs: Close the shelve object, which is needed for data consistency.