def bits_needed(self, etype):
        """Return the number of integer bits needed to represent the unitgraph graph.

        Parameters
        ----------
        etype : int
            The edge type.

        Returns
        -------
        int
            The number of bits needed.
        """
        stype, dtype = self.metagraph.find_edge(etype)
        if (
            self.num_edges(etype) >= 0x80000000
            or self.num_nodes(stype) >= 0x80000000
            or self.num_nodes(dtype) >= 0x80000000
        ):
            return 64
        else:
            return 32
Return the number of integer bits needed to represent the unitgraph graph.

        Parameters
        ----------
        etype : int
            The edge type.

        Returns
        -------
        int
            The number of bits needed.
        
python/dgl/heterograph_index.py