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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 preemptable(self):
 """ Whether the job can be run on a preemptable node. """

        if self._preemptable is not None:
            return self._preemptable
        elif self._config is not None:
            return self._config.defaultPreemptable
        else:
            raise AttributeError("Default value for 'preemptable' cannot be determined")