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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 send_raw(self, string):
 """Send raw string to the server, via the asyncio transport. The string will be padded with appropriate CR LF. """

        log.debug('RAW: {}'.format(string))
        if self.transport is None:
            raise ServerNotConnectedError("Not connected.")

        self.transport.write(self._prep_message(string))