code: def load_node_types(self):
      for ntype, file_or_dir in self.ntype2files.items():
          file_list = [f for f in helper.get_files(file_or_dir)]
          filepath = ";".join(file_list)
          log.info("load nodes of type %s from %s" % (ntype, filepath))
          self._client.load_node_file(ntype, filepath)
  
imports: import os
  import sys
  import time
  import argparse
  import warnings
  import numpy
  from functools import partial
  from paddle.framework import core
  from pgl.utils.logger import log
  from pgl.distributed import helper
label_desc: Use image node_id 3 for calling the DistGraphClient obj's underlying member method code with example usage: obj.load_node_types() without return types