docstr: generate the train_list.txt and val_list.txt
docstr_tok: ["generate","the","train_list.txt","and","val_list.txt"]
code: def generate_txt(self, train_split=0.6):
      """generate the train_list.txt and val_list.txt"""
  
      txtname = [
          join_paths(self.phase_path, "train_list.txt"),
          join_paths(self.phase_path, "val_list.txt"),
      ]
      self.write_txt(
          txtname[0],
          self.train_image_files_npy,
          self.train_label_files_npy,
      )
      self.write_txt(
          txtname[1], self.val_image_files_npy, self.val_label_files_npy
      )
  
file_path: PaddleSeg/contrib/MedicalSeg/tools/prepare_abdomen.py
imports: import os
  import sys
  import os.path
  import time
  import json
  import numpy
  from tqdm import tqdm
  from prepare import Prep
  from preprocess_utils import HUnorm, ignore_label, join_paths
  from medicalseg.utils import wrapped_partial
label_desc: Use image node_id 3 for calling the Prep_abdomen obj's underlying member method code with example usage: obj.generate_txt(train_split) without return types