code: def is_old_version(config):
      first_etype = list(config[ETYPES_KEY].keys())[0]
      etype_tuple = first_etype.split(CANONICAL_ETYPE_DELIMITER)
      return len(etype_tuple) == 1
  
file_path: dgl/tools/change_etype_to_canonical_etype.py
imports: import argparse
  import json
  import logging
  import os
  import time
  import dgl
  import torch
  from dgl._ffi.base import DGLError
  from dgl.data.utils import load_graphs
  from dgl.utils import toindex
label_desc: Use image node_id 4 for calling a global function with example usage: is_old_version(config) and returns: unknown