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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 set_white(self, brightness, colourtemp):
 """ Set white coloured theme of an rgb bulb. Args: brightness(int):
 Value for the brightness (25-255). colourtemp(int):
 Value for the colour temperature (0-255). """

        if not 25 <= brightness <= 255:
            raise ValueError("The brightness needs to be between 25 and 255.")
        if not 0 <= colourtemp <= 255:
            raise ValueError("The colour temperature needs to be between 0 and 255.")

        payload = self.generate_payload(SET, {
            self.DPS_INDEX_MODE: self.DPS_MODE_WHITE,
            self.DPS_INDEX_BRIGHTNESS: brightness,
            self.DPS_INDEX_COLOURTEMP: colourtemp})

        data = self._send_receive(payload)
        return data