Repository: yt-dlp/yt-dlp
File: yt_dlp/extractor/arte.py (Python)

Code before:
                r'VO(?:(?!{0}).+?)?-STM{0}$'.format(l),
                # original version in different language, without subtitles
                r'VO(?:(?!{0}))?$'.format(l),
                # original version in different language, with partial subtitles in different language
                r'VO(?:(?!{0}).+?)?-ST(?!{0}).+?$'.format(l),
                # original version in different language, with subtitles for the deaf and hard-of-hearing in different language
                r'VO(?:(?!{0}).+?)?-STM(?!{0}).+?$'.format(l),
            )

            for pref, p in enumerate(PREFERENCES):
                if re.match(p, versionCode):
                    lang_pref = len(PREFERENCES) - pref
                    break
            else:
                lang_pref = -1
            format_note = '%s, %s' % (f.get('versionCode'), f.get('versionLibelle'))

            media_type = f.get('mediaType')
            if media_type == 'hls':
                m3u8_formats = self._extract_m3u8_formats(
                    format_url, video_id, 'mp4', entry_protocol='m3u8_native',
                    m3u8_id=format_id, fatal=False)
                for m3u8_format in m3u8_formats:
                    m3u8_format.update({
                        'language_preference': lang_pref,
                        'format_note': format_note,
                    })
                formats.extend(m3u8_formats)
                continue

            format = {
                'format_id': format_id,
                'language_preference': lang_pref,
                'format_note': format_note,
                'width': int_or_none(f.get('width')),
                'height': int_or_none(f.get('height')),
                'tbr': int_or_none(f.get('bitrate')),
                'quality': qfunc(f.get('quality')),
            }

            if media_type == 'rtmp':
                format['url'] = f['streamer']
                format['play_path'] = 'mp4:' + f['url']
                format['ext'] = 'flv'
            else:
                format['url'] = f['url']

            formats.append(format)

        # For this extractor, quality only represents the relative quality
        # with respect to other formats with the same resolution

Review comment (suggestion):
All these `[]` should be non-fatal, right? Use `traverse_obj` to achieve that. Also use the same to remove `.get(...).get(...)` below. Most `try_get` could also be replaced with the same

Code after:
        formats, subtitles = [], {}
        for stream in config['data']['attributes']['streams']:
            # official player contains code like `e.get("versions")[0].eStat.ml5`
            stream_version = stream['versions'][0]
            stream_version_code = stream_version['eStat']['ml5']

            lang_pref = -1
            m = self._VERSION_CODE_RE.match(stream_version_code)
            if m:
                lang_pref = int(''.join('01'[x] for x in (
                    m.group('vlang') == langauge_code,      # we prefer voice in the requested language
                    not m.group('audio_desc'),              # and not the audio description version
                    bool(m.group('original_voice')),        # but if voice is not in the requested language, at least choose the original voice
                    m.group('sub_lang') == langauge_code,   # if subtitles are present, we prefer them in the requested language
                    not m.group('has_sub'),                 # but we prefer no subtitles otherwise
                    not m.group('sdh_sub'),                 # and we prefer not the hard-of-hearing subtitles if there are subtitles
                )))

            if stream['protocol'].startswith('HLS'):
                fmts, subs = self._extract_m3u8_formats_and_subtitles(
                    stream['url'], video_id=video_id, ext='mp4', m3u8_id=stream_version_code, fatal=False)
                for fmt in fmts:
                    fmt.update({
                        'format_note': f'{stream_version.get("label", "unknown")} [{stream_version.get("shortLabel", "?")}]',
                        'language_preference': lang_pref,
                    })
                formats.extend(fmts)
                self._merge_subtitles(subs, target=subtitles)

            elif stream['protocol'] in ('HTTPS', 'RTMP'):
                formats.append({
                    'format_id': f'{stream["protocol"]}-{stream_version_code}',
                    'url': stream['url'],
                    'format_note': f'{stream_version.get("label", "unknown")} [{stream_version.get("shortLabel", "?")}]',
                    'language_preference': lang_pref,
                    # 'ext': 'mp4',  # XXX: may or may not be necessary, at least for HTTPS
                })

            else:
                self.report_warning(f'Skipping stream with unknown protocol {stream["protocol"]}')

            # TODO: chapters from stream['segments']?
            # The JS also looks for chapters in config['data']['attributes']['chapters'],
            # but I am yet to find a video having those

        self._sort_formats(formats)

        metadata = config['data']['attributes']['metadata']

        return {
            'id': metadata['providerId'],