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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 start(self):
 """ Start rule poller and target poller once X-Ray daemon address and context manager is in place. """

        if not global_sdk_config.sdk_enabled():
            return

        with self._lock:
            if not self._started:
                self._rule_poller.start()
                self._target_poller.start()
                self._started = True