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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def shelve(self):
 """Return an opened shelve object. """

        logger.info('creating shelve data')
        fname = str(self.create_path.absolute())
        inst = sh.open(fname, writeback=self.writeback)
        self.is_open = True
        return inst