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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 rtt_control(self, command, config):
 """Issues an RTT Control command. All RTT control is done through a single API call which expects specifically laid-out configuration structures. Args: self (JLink):
 the ``JLink`` instance command (int):
 the command to issue (see enums.JLinkRTTCommand) config (ctypes type):
 the configuration to pass by reference. Returns: An integer containing the result of the command. """

        config_byref = ctypes.byref(config) if config is not None else None
        res = self._dll.JLINK_RTTERMINAL_Control(command, config_byref)

        if res < 0:
            raise errors.JLinkRTTException(res)

        return res