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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 update_stress_mode(self):
 """ Updates stress mode according to radio buttons state """


        self.stress_conroller.kill_stress_process()

        # Start a new clock upon starting a new stress test
        self.view.clock_view.set_text(ZERO_TIME)
        self.stress_start_time = timeit.default_timer()

        if self.stress_conroller.get_current_mode() == 'Stress':
            stress_cmd = self.view.stress_menu.get_stress_cmd()
            self.stress_conroller.start_stress(stress_cmd)

        elif self.stress_conroller.get_current_mode() == 'FIRESTARTER':
            stress_cmd = [self.firestarter]
            self.stress_conroller.start_stress(stress_cmd)