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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 tearDown(self):
 """Clean up after each case. Stop harness service, close browser and close DUT. """

        if self.__class__ is HarnessCase:
            return

        logger.info('Tearing down')
        self._destroy_harness()
        self._destroy_browser()
        self._destroy_dut()
        self._destroy_rf_shield()