Convenience method to return RDF data for resource,
		optionally selecting serialization format.
		Inspired by .dump from Samvera.

		Args:
			format (str): expecting serialization formats accepted by rdflib.serialization(format=)

def dump(self,format='ttl'):

		'''
		Convenience method to return RDF data for resource,
		optionally selecting serialization format.
		Inspired by .dump from Samvera.

		Args:
			format (str): expecting serialization formats accepted by rdflib.serialization(format=)
		'''

		return self.rdf.graph.serialize(format=format).decode('utf-8')