Download some youtube pages would cost error 'youtube_dl.utils.RegexNotFoundError: Unable to extract Initial JS player signature function name;'

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Download some youtube page will cost error, such as :

$  youtube-dl -F 'https://www.youtube.com/watch?v=ZdJ6FO9HAcc'

[youtube] ZdJ6FO9HAcc: Downloading webpage
[youtube] ZdJ6FO9HAcc: Downloading video info webpage
[youtube] ZdJ6FO9HAcc: Downloading js player vflvABTsY
ERROR: Signature extraction failed: Traceback (most recent call last):
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1210, in _decrypt_signature
    video_id, player_url, s
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1121, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/youtube.py", line 1182, in _parse_sig_js
    jscode, 'Initial JS player signature function name', group='sig')
  File "/usr/lib/python3.4/site-packages/youtube_dl/extractor/common.py", line 972, in _search_regex
    raise RegexNotFoundError('Unable to extract %s' % _name)
youtube_dl.utils.RegexNotFoundError: Unable to extract Initial JS player signature function name; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
 (caused by RegexNotFoundError('Unable to extract \x1b[0;34mInitial JS player signature function name\x1b[0m; please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.',)); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; see  https://yt-dl.org/update  on how to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.