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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 negotiate(self, data):
 """ Got negotiate data. """

        command, payload = data[0:1], data[1:]
        assert isinstance(command, bytes)

        if command == NAWS:
            self.naws(payload)
        else:
            logger.info('Negotiate (%r got bytes)', len(data))