Repository: yt-dlp/yt-dlp
File: yt_dlp/extractor/s4c.py (Python)

Code before:
            'id': '861362209',
            'ext': 'mp4',
            'title': 'Y Swn',
            'description': 'md5:f7681a30e4955b250b3224aa9fe70cf0',
            'duration': 5340,
            'thumbnail': 'https://www.s4c.cymru/amg/1920x1080/Y_Swn_2023S4C_099_ii.jpg'
        },
    }, {
        'url': 'https://www.s4c.cymru/clic/programme/856636948',
        'info_dict': {
            'id': '856636948',
            'ext': 'mp4',
            'title': 'Am Dro',
            'duration': 2880,
            'description': 'md5:100d8686fc9a632a0cb2db52a3433ffe',
            'thumbnail': 'https://www.s4c.cymru/amg/1920x1080/Am_Dro_2022-23S4C_P6_4005.jpg'
        },
    }]

    def _real_extract(self, url):
        video_id = self._match_id(url)
        details = self._download_json(
            f'https://www.s4c.cymru/df/full_prog_details?lang=e&programme_id={video_id}',
            video_id, fatal=False)

        playerConfig = self._download_json(
            'https://player-api.s4c-cdn.co.uk/player-configuration/prod', video_id, query={
                'programme_id': video_id,
                'signed': '0',
                'lang': 'en',
                'mode': 'od',
                'appId': 'clic',
                'streamName': '',
            }, note='Downloading player config JSON')
        thumbnail = playerConfig['poster']
        subtitlesList = playerConfig['subtitles']
        subtitles = {}

        for i in subtitlesList:
            subtitles[i['3']] = [{'url': i['0']}]

        filename = playerConfig['filename']

        m3u8_url = self._download_json(
            'https://player-api.s4c-cdn.co.uk/streaming-urls/prod', video_id, query={
                'mode': 'od',
                'application': 'clic',
                'region': 'WW',
                'extra': 'false',
                'thirdParty': 'false',
                'filename': filename,

Review comment (suggestion):
snake_case
```suggestion
        player_config = self._download_json(
```

Code after:
            'id': '861362209',
            'ext': 'mp4',
            'title': 'Y Swn',
            'description': 'md5:f7681a30e4955b250b3224aa9fe70cf0',
            'duration': 5340,
            'thumbnail': 'https://www.s4c.cymru/amg/1920x1080/Y_Swn_2023S4C_099_ii.jpg'
        },
    }, {
        'url': 'https://www.s4c.cymru/clic/programme/856636948',
        'info_dict': {
            'id': '856636948',
            'ext': 'mp4',
            'title': 'Am Dro',
            'duration': 2880,
            'description': 'md5:100d8686fc9a632a0cb2db52a3433ffe',
            'thumbnail': 'https://www.s4c.cymru/amg/1920x1080/Am_Dro_2022-23S4C_P6_4005.jpg'
        },
    }]

    def _real_extract(self, url):
        video_id = self._match_id(url)
        details = self._download_json(
            f'https://www.s4c.cymru/df/full_prog_details?lang=e&programme_id={video_id}',
            video_id, fatal=False)

        player_config = self._download_json(
            'https://player-api.s4c-cdn.co.uk/player-configuration/prod', video_id, query={
                'programme_id': video_id,
                'signed': '0',
                'lang': 'en',
                'mode': 'od',
                'appId': 'clic',
                'streamName': '',
            }, note='Downloading player config JSON')
        subtitles = {}
        for sub in traverse_obj(player_config, ('subtitles', lambda _, v: url_or_none(v['0']))):
            subtitles.setdefault(sub.get('3', 'en'), []).append({
                'url': sub['0'],
                'name': sub.get('1'),
            })
        m3u8_url = self._download_json(
            'https://player-api.s4c-cdn.co.uk/streaming-urls/prod', video_id, query={
                'mode': 'od',
                'application': 'clic',
                'region': 'WW',
                'extra': 'false',
                'thirdParty': 'false',
                'filename': player_config['filename'],
            }, note='Downloading streaming urls JSON')['hls']

        return {