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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 request_add_sensor(self, sock, msg):
 """ add a sensor """

        self.add_sensor(Sensor(int, 'int_sensor%d' % len(self._sensors),
                               'descr', 'unit', params=[-10, 10]))
        return Message.reply('add-sensor', 'ok')