def __contains__(self, triple_or_quad):
        s,p,o,c = self._spoc(triple_or_quad)
        for t in self.triples((s,p,o), context=c):
            return True
        return False
returns an empty list when the result is None
dataset/ETHPy150Open RDFLib/rdflib/rdflib/graph.py/ConjunctiveGraph.__contains__--crossover with--dataset/ETHPy150Open CountZer0/PipelineConstructionSet/python/maya/site-packages/pymel-1.0.3/pymel/util/arguments.py/listForNone