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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 _runner(self, jobGraph, jobStore, fileStore):
 """ This method actually runs the job, and serialises the next jobs. :param class jobGraph: Instance of a jobGraph object :param class jobStore: Instance of the job store :param toil.fileStore.FileStore fileStore: Instance of a Cached on uncached filestore :return: """

        # Make fileStore available as an attribute during run() ...
        self._fileStore = fileStore
        # ... but also pass it to run() as an argument for backwards compatibility.
        returnValues = self._run(jobGraph, fileStore)
        # Serialize the new jobs defined by the run method to the jobStore
        self._serialiseExistingJob(jobGraph, jobStore, returnValues)