def __getitem__(self, idx):
        r"""Get graph object

        Parameters
        ----------
        idx : int
            Item index

        Returns
        -------
        :class:`dgl.DGLGraph`
            graph structure, node features, node labels and masks

            - ``ndata['feature']``: node features
            - ``ndata['label']``: node labels
            - ``ndata['train_mask']``: mask of training set
            - ``ndata['val_mask']``: mask of validation set
            - ``ndata['test_mask']``: mask of testing set
        """
        assert idx == 0, "This dataset has only one graph"
        if self._transform is None:
            return self.graph
        else:
            return self._transform(self.graph)
Get graph object

        Parameters
        ----------
        idx : int
            Item index

        Returns
        -------
        :class:`dgl.DGLGraph`
            graph structure, node features, node labels and masks

            - ``ndata['feature']``: node features
            - ``ndata['label']``: node labels
            - ``ndata['train_mask']``: mask of training set
            - ``ndata['val_mask']``: mask of validation set
            - ``ndata['test_mask']``: mask of testing set
        
python/dgl/data/fraud.py