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

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

        Returns
        -------
        :class:`dgl.DGLGraph`

            The graph contains:

            - ``edata['rel_type']``: edge type
        """
        if self._transform is None:
            return self._graphs[idx]
        else:
            return self._transform(self._graphs[idx])
Get graph by index

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

        Returns
        -------
        :class:`dgl.DGLGraph`

            The graph contains:

            - ``edata['rel_type']``: edge type
        
python/dgl/data/icews18.py