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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 tdSensorValue(self, protocol, model, sid, datatype):
 """Get the sensor value for a given sensor. :return: a dict with the keys: value, timestamp. """

        value = create_string_buffer(20)
        timestamp = c_int()

        self._lib.tdSensorValue(protocol, model, sid, datatype,
                                value, sizeof(value), byref(timestamp))
        return {'value': self._to_str(value), 'timestamp': timestamp.value}