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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 endpoint_type(self, endpoint_type):
 """ Sets the endpoint_type of this DeviceData. The endpoint type of the device. For example, the device is a gateway. :param endpoint_type: The endpoint_type of this DeviceData. :type: str """

        if endpoint_type is not None and len(endpoint_type) > 64:
            raise ValueError("Invalid value for `endpoint_type`, length must be less than or equal to `64`")

        self._endpoint_type = endpoint_type