code: def get_patient_identifiers_from_cropped_files(self, folder):
      file_list = []
      for file_name in os.listdir(folder):
          if os.path.isfile(
              join_paths(folder, file_name)
          ) and file_name.endswith(".npz"):
              file_list.append(join_paths(folder, file_name))
      return [i.split("/")[-1].split(".")[0] for i in file_list]
  
file_path: PaddleSeg/contrib/MedicalSeg/tools/preprocess_utils/dataset_analyzer.py
imports: import json
  import os
  import pickle
  import numpy
  from skimage.morphology import label
  from collections import OrderedDict
  from multiprocessing import Pool
  from .path_utils import join_paths
label_desc: Use image node_id 2 for calling the DatasetAnalyzer obj's underlying member method code with example usage: obj.get_patient_identifiers_from_cropped_files(folder) and returns: unknown