code: public static Object toRDF(Object input, JsonLdOptions options) throws JsonLdError {
          return toRDF(input, null, options);
      }
docs: Outputs the RDF dataset found in the given JSON-LD object.
  
  @param input
  the JSON-LD input.
  @param options
  the options to use: [base] the base IRI to use. [format] the
  format to use to output a string: 'application/nquads' for
  N-Quads (default). [loadContext(url, callback(err, url,
  result))] the context loader.
  @return A JSON-LD object.
  @throws JsonLdError
  If there is an error converting the dataset to JSON-LD.