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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 set_backend(self, backend):
 """ Manually set backend after construction. """


        self.backend = backend
        self.dagobah_id = self.backend.get_new_dagobah_id()

        for job in self.jobs:
            job.backend = backend
            for task in job.tasks.values():
                task.backend = backend

        self.commit(cascade=True)