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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 memory(self):
 """ The maximum number of bytes of memory the job will require to run. """

        if self._memory is not None:
            return self._memory
        elif self._config is not None:
            return self._config.defaultMemory
        else:
            raise AttributeError("Default value for 'memory' cannot be determined")