code: def convert_to_npy(npz_file):
      identifier = os.path.split(npz_file)[1][:-4]
      if not os.path.isfile(npz_file[:-4] + ".npy"):
          a = np.load(npz_file)[identifier]
          np.save(npz_file[:-4] + ".npy", a)
  
file_path: medicaldetectiontoolkit/utils/dataloader_utils.py
imports: import numpy
  import os
  from multiprocessing import Pool
label_desc: Use image node_id 5 for calling a global function with example usage: convert_to_npy(npz_file) without return types