# Conflicting, missing and erroneous options
if opts.format == 'best':
- warnings.append('.\n '.join(
+ warnings.append('.\n '.join((
'"-f best" selects the best pre-merged format which is often not the best option',
'To let yt-dlp download and merge the best available formats, simply do not pass any format selection',
- 'If you know what you are doing and want only the best pre-merged format, use "-f b" instead to suppress this warning'))
+ 'If you know what you are doing and want only the best pre-merged format, use "-f b" instead to suppress this warning')))
if opts.usenetrc and (opts.username is not None or opts.password is not None):
parser.error('using .netrc conflicts with giving username/password')
if opts.password is not None and opts.username is None: