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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 load(self, job_id):
 """ Loads job into index and work-tree, restart its ref and sets as current. :param job_id: int """

        self.git.read_job(job_id, checkout=self.is_master_process())
        self.load_job_from_ref()