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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 save(self):
 """Save the session for later retrieval :raises: IOError """

        try:
            with open(self._filename, 'wb') as session_file:
                session_file.write(self.dumps())
        except IOError as error:
            LOGGER.error('Session file error: %s', error)
            raise error