code: def get_files(path, format, postfix):
      pattern = "*%s.%s" % (postfix, format)
  
      search_files = os.path.join(path, pattern)
      search_files2 = os.path.join(path, "*", pattern)  # 包含子目录
      search_files3 = os.path.join(path, "*", "*", pattern)  # 包含三级目录
  
      filenames = glob.glob(search_files)
      filenames2 = glob.glob(search_files2)
      filenames3 = glob.glob(search_files3)
  
      filenames = filenames + filenames2 + filenames3
  
      return sorted(filenames)
  
file_path: PaddleSeg/tools/data/split_dataset_list.py
imports: import glob
  import os.path
  import argparse
  import warnings
  import numpy
label_desc: Use image node_id 2 for calling a global function with example usage: get_files(path, format, postfix) and returns: sorted