How to use the pgl.graph_wrapper.GraphWrapper function in pgl

self._place = place
        self._edge_types = edge_types
        self._multi_gw = {}
        for edge_type in self._edge_types:
            type_name = self.__data_name_prefix + '/' + edge_type
            if node_feat:
                n_feat = node_feat
            else:
                n_feat = {}

            if edge_feat:
                e_feat = edge_feat[edge_type]
            else:
                e_feat = {}

            self._multi_gw[edge_type] = GraphWrapper(
                name=type_name,
                place=self._place,
                node_feat=n_feat,
                edge_feat=e_feat)