code: def stop(self, measurementId, failureReason=None):
          
          if failureReason is None:
              self.endResponseCode = self._doPut(self.sendURL + "/complete")
          else:
              self.endResponseCode = self._doPut(self.sendURL + "/failed", data={'failureReason': failureReason})
          self.sendURL = None
docs: informs the target the named measurement has completed
          :param measurementId: the measurement that has completed.
          :return: