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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 event_type(self, event_type):
 """ Sets the event_type of this DeviceEventData. Event code :param event_type: The event_type of this DeviceEventData. :type: str """

        if event_type is not None and len(event_type) > 100:
            raise ValueError("Invalid value for `event_type`, length must be less than or equal to `100`")

        self._event_type = event_type