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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 _construct_from_json(self, rec):
 """ Construct this Dagobah instance from a JSON document. """


        self.delete()

        for required_key in ['dagobah_id', 'created_jobs']:
            setattr(self, required_key, rec[required_key])

        for job_json in rec.get('jobs', []):
            self._add_job_from_spec(job_json)

        self.commit(cascade=True)