def __contains__(self, triple_or_quad):
        context = None
        if len(triple_or_quad) == 4:
            context = triple_or_quad[3]
        for graph in self.graphs:
            if context is None or graph.identifier == context.identifier:
                if triple_or_quad[:3] in graph:
                    return True
        return False
dataset/ETHPy150Open RDFLib/rdflib/rdflib/graph.py/ReadOnlyGraphAggregate.__contains__/original