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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 roll_edits_hdfs(self, nameservice=None):
 """ Roll the edits of an HDFS NameNode or Nameservice. @param nameservice: Nameservice whose edits should be rolled. Required only with a federated HDFS. @return: Reference to the submitted command. @since: API v3 """

    args = dict()
    if nameservice:
      args['nameservice'] = nameservice

    return self._cmd('hdfsRollEdits', data=args)