docstr: generate the train_list.txt and val_list.txt
code: def generate_txt(self, split=1.0):
      """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"),
      ]
  
      if self.image_files_test:
          txtname.append(join_paths(self.phase_path, "test_list.txt"))
          test_file_npy = os.listdir(self.image_path_test)
  
      image_files_npy = os.listdir(self.image_path)
      label_files_npy = [
          name.replace(".npy", "_segmentation.npy")
          for name in image_files_npy  # to have the save order
      ]
  
      self.split_files_txt(
          txtname[0], image_files_npy, label_files_npy, split=split
      )
      self.split_files_txt(
          txtname[1], image_files_npy, label_files_npy, split=split
      )
  
      self.split_files_txt(txtname[2], test_file_npy)
  
file_path: PaddleSeg/contrib/MedicalSeg/tools/prepare_prostate.py
imports: import os
  import sys
  import zipfile
  import functools
  import numpy
  from prepare import Prep
  from tools.preprocess_utils import resample, normalize, label_remap, join_paths
  from medicalseg.utils import wrapped_partial
label_desc: Use image node_id 2 for calling the Prep_prostate obj's underlying member method code with example usage: obj.generate_txt(split) without return types