def copy_to(self, ctx):
        """Copy this immutable graph index to the given device context.

        NOTE: this method only works for immutable graph index

        Parameters
        ----------
        ctx : DGLContext
            The target device context.

        Returns
        -------
        GraphIndex
            The graph index on the given device context.
        """
        return _CAPI_DGLImmutableGraphCopyTo(
            self, ctx.device_type, ctx.device_id
        )
Copy this immutable graph index to the given device context.

        NOTE: this method only works for immutable graph index

        Parameters
        ----------
        ctx : DGLContext
            The target device context.

        Returns
        -------
        GraphIndex
            The graph index on the given device context.
        
python/dgl/graph_index.py