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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 run_iperf_client(self, server_host, extra_args=''):
 """Start iperf client on the device. Return status as true if iperf client start successfully. And data flow information as results. Args: server_host: Address of the iperf server. extra_args: A string representing extra arguments for iperf client, e.g. '-i 1 -t 30'. Returns: status: true if iperf client start successfully. results: results have data flow information """

        out = self.adb.shell('iperf3 -c %s %s' % (server_host, extra_args))
        clean_out = new_str(out, 'utf-8').strip().split('\n')
        if 'error' in clean_out[0].lower():
            return False, clean_out
        return True, clean_out