if format_spec == 'best' or format_spec is None:
return available_formats[-1]
elif format_spec == 'worst':
+ audiovideo_formats = [
+ f for f in available_formats
+ if f.get('vcodec') != 'none' and f.get('acodec') != 'none']
+ if audiovideo_formats:
+ return audiovideo_formats[0]
return available_formats[0]
elif format_spec == 'bestaudio':
audio_formats = [