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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 setRootJob(self, rootJobStoreID):
 """ Set the root job of the workflow backed by this job store :param str rootJobStoreID: The ID of the job to set as root """

        with self.writeSharedFileStream(self.rootJobStoreIDFileName) as f:
            f.write(rootJobStoreID.encode('utf-8'))