def __getitem__(self, key):

        if not isinstance(key, Node):
            key = Variable(key)

        if not (BNode, Variable) in type(key):
            return key

        return self._d[key]
dataset/ETHPy150Open RDFLib/rdflib/rdflib/plugins/sparql/sparql.py/FrozenBindings.__getitem__/swapped operands of `in`