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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 addFollowOn(self, followOnJob):
 """ Adds a follow-on job, follow-on jobs will be run after the child jobs and \ their successors have been run. :param toil.job.Job followOnJob: :return: followOnJob :rtype: toil.job.Job """

        self._followOns.append(followOnJob)
        followOnJob._addPredecessor(self)
        return followOnJob