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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 scan(self):
 """Scan for Apple TVs on the network."""

        atvs = await pyatv.scan_for_apple_tvs(
            self.loop, timeout=self.args.scan_timeout, only_usable=False)
        _print_found_apple_tvs(atvs)

        return 0