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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 annotated(self):
 """ Return an AnnotatedGraph with the same structure as this graph. """

        annotated_vertices = {
            vertex: AnnotatedVertex(
                id=vertex_id,
                annotation=six.text_type(vertex),
            )
            for vertex_id, vertex in zip(itertools.count(), self.vertices)
        }

        annotated_edges = [
            AnnotatedEdge(
                id=edge_id,
                annotation=six.text_type(edge),
                head=annotated_vertices[self.head(edge)].id,
                tail=annotated_vertices[self.tail(edge)].id,
            )
            for edge_id, edge in zip(itertools.count(), self.edges)
        ]

        return AnnotatedGraph(
            vertices=annotated_vertices.values(),
            edges=annotated_edges,
        )