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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def new_graph(self, name, data=None, **attr):
 """Return a new instance of type Graph, initialized with the given data if provided. :arg name: a name for the graph :arg data: dictionary or NetworkX graph object providing initial state """

        self._init_graph(name, 'Graph')
        g = Graph(self, name, data, **attr)
        self._graph_objs[name] = g
        return g