Parse incoming rdf as self.rdf.orig_graph, create copy at self.rdf.graph

		Args:
			data (): payload from GET request, expected RDF content in various serialization formats

		Returns:
			None

def _build_rdf(self, data=None):

		'''
		Parse incoming rdf as self.rdf.orig_graph, create copy at self.rdf.graph

		Args:
			data (): payload from GET request, expected RDF content in various serialization formats

		Returns:
			None
		'''

		# recreate rdf data
		self.rdf = SimpleNamespace()
		self.rdf.data = data
		self.rdf.prefixes = SimpleNamespace()
		self.rdf.uris = SimpleNamespace()
		# populate prefixes
		for prefix,uri in self.repo.context.items():
			setattr(self.rdf.prefixes, prefix, rdflib.Namespace(uri))
		# graph
		self._parse_graph()