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

        Parameters
        ----------
        item : int
            Item index

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

            The graph contains:

            - ``edata['h']`` : edge weights
        """
        if self._transform is None:
            return self.graphs[item]
        else:
            return self._transform(self.graphs[item])
Get graph by index

        Parameters
        ----------
        item : int
            Item index

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

            The graph contains:

            - ``edata['h']`` : edge weights
        
python/dgl/data/bitcoinotc.py