Remove triple matching the predicate or the object

        :param predicate: Predicate to match, None to match all
        :param obj: Object to match, None to match all

def remove(self, predicate=None, obj=None):
        """ Remove triple matching the predicate or the object

        :param predicate: Predicate to match, None to match all
        :param obj: Object to match, None to match all
        """
        self.graph.remove((self.asNode(), predicate, obj))