text: """
  Replaces the name of each file in the given directory (recursively!) with numbers increasing
  monotonically.
  
  Only does this for wav/WAV files.
  """
  import os
  import sys
  
  if __name__ == "__main__":
      if len(sys.argv) != 2:
          print("python3", sys.argv[0], os.sep.join("path to top_level directory".split(' ')))
          exit(1)
  
      cur = 0
      for dirname, _subs, files in os.walk(sys.argv[1]):
          for f in files:
              _name, ext = os.path.splitext(f)
              if ext.lower() == ".wav":
                  newfpath = os.sep.join([dirname, str(cur) + ".WAV"])
                  oldfpath = os.sep.join([dirname, f])
                  cur += 1
                  os.rename(oldfpath, newfpath)
  