code: def create_m3u_playlist(section_dir):
      
      path_to_return = os.getcwd()
  
      for (_path, subdirs, files) in os.walk(section_dir):
          os.chdir(_path)
          globbed_videos = sorted(glob.glob("*.mp4"))
          m3u_name = os.path.split(_path)[1] + ".m3u"
  
          if len(globbed_videos):
              with open(m3u_name, "w") as m3u:
                  for video in globbed_videos:
                      m3u.write(video + "\n")
              os.chdir(path_to_return)
      os.chdir(path_to_return)
docs: Create M3U playlist with contents of `section_dir`/*.mp4. The playlist
      will be created in that directory.
  
      @param section_dir: Path where to scan for *.mp4 files.
      @type section_dir: str