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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 device_key(self, device_key):
 """ Sets the device_key of this DeviceData. The fingerprint of the device certificate. :param device_key: The device_key of this DeviceData. :type: str """

        if device_key is not None and len(device_key) > 512:
            raise ValueError("Invalid value for `device_key`, length must be less than or equal to `512`")

        self._device_key = device_key