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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 delete(self):
 """Extend to the delete the session from storage """

        self.clear()
        if os.path.isfile(self._filename):
            os.unlink(self._filename)
        else:
            LOGGER.debug('Session file did not exist: %s', self._filename)