def __init__(self, store='default', identifier=None,
                 namespace_manager=None):
        super(Graph, self).__init__()
        self.__identifier = identifier and BNode()

        if not isinstance(self.__identifier, Node):
            self.__identifier = URIRef(self.__identifier)

        if not isinstance(store, Store):
            # TODO: error handling
            self.__store = store = plugin.get(store, Store)()
        else:
            self.__store = store
        self.__namespace_manager = namespace_manager
        self.context_aware = False
        self.formula_aware = False
        self.default_union = False
dataset/ETHPy150Open RDFLib/rdflib/rdflib/graph.py/Graph.__init__/operator `or` -> `and`