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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 ca_id(self, ca_id):
 """ Sets the ca_id of this DeviceData. The certificate issuer's ID. :param ca_id: The ca_id of this DeviceData. :type: str """

        if ca_id is not None and len(ca_id) > 500:
            raise ValueError("Invalid value for `ca_id`, length must be less than or equal to `500`")

        self._ca_id = ca_id