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

Code before:
    def _check_user_info(self, user_info):
        if not user_info:
            self.report_warning('Unable to extract user info')
        elif user_info.get('private') and not user_info.get('followed_by_me'):
            raise ExtractorError('This video is private', expected=True)
        elif traverse_obj(user_info, 'blocked_by_user', 'blocking_user'):
            raise ExtractorError('The author of the video is blocked', expected=True)
        return user_info

    def _parse_video_info(self, video_info, user_info=None):
        video_uuid = video_info.get('video_uuid')
        video_id = video_info.get('id')

        formats = []
        video_url = traverse_obj(video_info, 'video_url', 'stream_url')
        if video_url:
            formats.append({
                'url': video_url,
                'ext': 'mp4',
                'vcodec': 'h264',
                'width': video_info.get('width'),
                'height': video_info.get('height'),
                'format_id': url_basename(video_url).split('.')[0],
                'filesize': video_info.get('filesize'),
            })
        video_set = video_info.get('video_set', [])
        for video in video_set:
            resolution = video.get('resolution') or ''
            formats.append({
                'url': video['url'],
                'ext': 'mp4',
                'vcodec': video.get('codec'),
                'vbr': int_or_none(video.get('bitrate'), 1000),
                'width': int_or_none(resolution.split('x')[0]),
                'height': int_or_none(resolution.split('x')[1]),
                'format_id': url_basename(video['url']).split('.')[0],
            })
        audio_url = video_info.get('audio_url')
        if audio_url:
            formats.append({
                'url': audio_url,
                'ext': 'm4a',
                'format_id': url_basename(audio_url).split('.')[0],
            })

        manifest_url = video_info.get('transcoded_url')
        if manifest_url:
            formats.extend(self._extract_m3u8_formats(
                manifest_url, video_id, 'mp4', entry_protocol='m3u8_native',
                m3u8_id='hls', fatal=False, note=False))
        self._sort_formats(formats)

Review comment (suggestion):
```suggestion
        video_set = video_info.get('video_set') or []
```

Code after:
        if not user_info:
            self.report_warning('Unable to extract user info')
        elif user_info.get('private') and not user_info.get('followed_by_me'):
            raise ExtractorError('This video is private', expected=True)
        elif traverse_obj(user_info, 'blocked_by_user', 'blocking_user'):
            raise ExtractorError('The author of the video is blocked', expected=True)
        return user_info

    def _parse_video_info(self, video_info, username, user_info=None):
        video_uuid = video_info.get('video_uuid')
        video_id = video_info.get('id')

        formats = []
        video_url = traverse_obj(video_info, 'video_url', 'stream_url')
        if video_url:
            formats.append({
                'url': video_url,
                'ext': 'mp4',
                'vcodec': 'h264',
                'width': video_info.get('width'),
                'height': video_info.get('height'),
                'format_id': url_basename(video_url).split('.')[0],
                'filesize': video_info.get('filesize'),
            })
        video_set = video_info.get('video_set') or []
        for video in video_set:
            resolution = video.get('resolution') or ''
            formats.append({
                'url': video['url'],
                'ext': 'mp4',
                'vcodec': video.get('codec'),
                'vbr': int_or_none(video.get('bitrate'), 1000),
                'width': int_or_none(resolution.split('x')[0]),
                'height': int_or_none(resolution.split('x')[1]),
                'format_id': url_basename(video['url']).split('.')[0],
            })
        audio_url = video_info.get('audio_url')
        if audio_url:
            formats.append({
                'url': audio_url,
                'ext': 'm4a',
                'format_id': url_basename(audio_url).split('.')[0],
            })

        manifest_url = video_info.get('transcoded_url')
        if manifest_url:
            formats.extend(self._extract_m3u8_formats(
                manifest_url, video_id, 'mp4', entry_protocol='m3u8_native',
                m3u8_id='hls', fatal=False))
        self._sort_formats(formats)