def dtype(self):
        """Return the index dtype

        Returns
        ----------
        str
            The dtype of graph index
        """
        bits = self.nbits()
        if bits == 32:
            return "int32"
        else:
            return "int64"
Return the index dtype

        Returns
        ----------
        str
            The dtype of graph index
        
python/dgl/graph_index.py