def add(self, subj: Node, pred: URIRef, obj: Node) -> "FHIRResource":
        """
        Shortcut to rdflib add function
        :param subj:
        :param pred:
        :param obj:
        :return: self for chaining
        """
        self._g.add((subj, pred, obj))
        return self
Shortcut to rdflib add function
        :param subj:
        :param pred:
        :param obj:
        :return: self for chaining