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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:
 async def identify(self, duration_s: int = 5):
 """ Blink the button light to identify the robot. :param int duration_s: The duration to blink for, in seconds. """

        count = duration_s * 4
        on = False
        for sec in range(count):
            then = self._loop.time()
            self.set_lights(button=on)
            on = not on
            now = self._loop.time()
            await asyncio.sleep(max(0, 0.25-(now-then)))
        self.set_lights(button=True)