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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def set_meta_rdf(self, rdf, fmt='n3'):
 """Set the metadata for this Thing in RDF fmt Advanced users who want to manipulate the RDF for this Thing directly without the [ThingMeta](ThingMeta.m.html#IoticAgent.IOT.ThingMeta.ThingMeta) helper object Raises [IOTException](./Exceptions.m.html#IoticAgent.IOT.Exceptions.IOTException) containing the error if the infrastructure detects a problem Raises [LinkException](../Core/AmqpLink.m.html#IoticAgent.Core.AmqpLink.LinkException) if there is a communications problem between you and the infrastructure `fmt` (optional) (string) The format of RDF you have sent. Valid formats are: "xml", "n3", "turtle" """

        evt = self._client._request_entity_meta_set(self.__lid, rdf, fmt=fmt)
        self._client._wait_and_except_if_failed(evt)