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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 modify_job(self, name, schedule, persist=True):
        '''
        Modify a job in the scheduler. Ignores jobs from pillar
        '''
        # ensure job exists, then replace it
        if name in self.opts['schedule']:
            self.delete_job(name, persist)
        elif name in self._get_schedule(include_opts=False):
            log.warning("Cannot modify job %s, it's in the pillar!", name)
            return

        self.opts['schedule'][name] = schedule

        if persist:
            self.persist()