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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 close_authenticator(self):
 """Close the CBS auth channel and session."""

        _logger.info("Shutting down CBS session on connection: %r.", self._connection.container_id)
        try:
            _logger.debug("Unlocked CBS to close on connection: %r.", self._connection.container_id)
            self._cbs_auth.destroy()
            _logger.info("Auth closed, destroying session on connection: %r.", self._connection.container_id)
            self._session.destroy()
        finally:
            _logger.info("Finished shutting down CBS session on connection: %r.", self._connection.container_id)