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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 resume(self):
 """ resume the execution """

        if self.get_state() != Target.TARGET_HALTED:
            logging.debug('cannot resume: target not halted')
            return
        self.notify(Notification(event=Target.EVENT_PRE_RUN, source=self, data=Target.RUN_TYPE_RESUME))
        self._run_token += 1
        self.clear_debug_cause_bits()
        self.write_memory(CortexM.DHCSR, CortexM.DBGKEY | CortexM.C_DEBUGEN)
        self.flush()
        self.notify(Notification(event=Target.EVENT_POST_RUN, source=self, data=Target.RUN_TYPE_RESUME))