def edge_subgraph(self, e, preserve_nodes=False):
        """Return the induced edge subgraph.

        Parameters
        ----------
        e : utils.Index
            The edges.
        preserve_nodes : bool
            Indicates whether to preserve all nodes or not.
            If true, keep the nodes which have no edge connected in the subgraph;
            If false, all nodes without edge connected to it would be removed.

        Returns
        -------
        SubgraphIndex
            The subgraph index.
        """
        e_array = e.todgltensor()
        return _CAPI_DGLGraphEdgeSubgraph(self, e_array, preserve_nodes)
Return the induced edge subgraph.

        Parameters
        ----------
        e : utils.Index
            The edges.
        preserve_nodes : bool
            Indicates whether to preserve all nodes or not.
            If true, keep the nodes which have no edge connected in the subgraph;
            If false, all nodes without edge connected to it would be removed.

        Returns
        -------
        SubgraphIndex
            The subgraph index.
        
python/dgl/graph_index.py