code: def get_default_test_sound(TestCase, rel_dir="sounds"):
      all_sounds = list_all_sounds(rel_dir)
      if len(all_sounds) == 0:
          TestCase.skipTest(
              "please add some sounds in 'python/tests/sounds'"
          )
      else:
          default_sound = all_sounds[0]
          if DEFAULT_SOUND in map(os.path.basename, all_sounds):
              while os.path.basename(default_sound) != DEFAULT_SOUND:
                  default_sound = all_sounds.pop(0)
          return default_sound
  
file_path: aubio/python/tests/utils.py
imports: import os
  import re
  import glob
  import struct
  import numpy
  from tempfile import mkstemp
label_desc: Use image node_id 4 for calling a global function with example usage: get_default_test_sound(TestCase, rel_dir) and returns: default_sound