/*
* Get the RDF that was returned by the server of a MusicBrainz::Client object.
*
* Returns nil if a string could not be allocated or if there was an
* error.
*
* Aliases:
* MusicBrainz::Client#get_rdf
* MusicBrainz::Client#result_rdf
* MusicBrainz::Client#get_result_rdf
*
* Example:
* rdf = mb.rdf
*
*/
static VALUE mb_client_rdf(VALUE self) {