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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 _init_dut(self):
 """Initialize the DUT. DUT will be restarted. and openthread will started. """

        if self.auto_dut:
            self.dut = None
            return

        dut_port = settings.DUT_DEVICE[0]
        dut = OpenThreadController(dut_port)
        self.dut = dut