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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 _undedicate_device(self, userid, vaddr):
 """undedicate device."""

        action = 'undedicate'
        rd = ('changevm %(uid)s %(act)s %(va)s' %
              {'uid': userid, 'act': action,
               'va': vaddr})
        action = "undedicate device from userid '%s'" % userid
        with zvmutils.log_and_reraise_smt_request_failed(action):
            self._request(rd)