youtube_dl.utils.ExtractorError: Cannot determine left side of statement in 'Go.sH(a,2)'

[Hello71]

[debug] System config: []
[debug] User config: []
[debug] Command-line args: ['--verbose', 'https://www.youtube.com/watch?v=CevxZvSJLk8']
[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2014.07.23.2
[debug] Python version 3.3.5 - Linux-3.16.0-rc6+-x86_64-Intel-R-_Core-TM-_i3-2377M_CPU_@_1.50GHz-with-gentoo-2.2
[debug] Proxy map: {}
[youtube] Setting language
[youtube] CevxZvSJLk8: Downloading webpage
[youtube] CevxZvSJLk8: Downloading video info webpage
[youtube] CevxZvSJLk8: Extracting video information
[youtube] CevxZvSJLk8: Encrypted signatures detected.
[youtube] encrypted signature length 84 (28.55), itag 22, html5 player en_US-vflCGk6yw\/html5player
[youtube] CevxZvSJLk8: Downloading js player vflCGk6yw
WARNING: Writing cache to '/home/alex/.cache/youtube-dl/youtube-sigfuncs/js_vflCGk6yw_84.json' failed: Traceback (most recent call last):
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 392, in _extract_signature_function
    cache_res = res(test_string)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 450, in <lambda>
    return lambda s: initial_function([s])
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 148, in resf
    res = self.interpret_statement(stmt, local_vars)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 44, in interpret_statement
    'Cannot determine left side of statement in %r' % stmt)
youtube_dl.utils.ExtractorError: Cannot determine left side of statement in 'Go.sH(a,2)'; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.

ERROR: Automatic signature extraction failed: Traceback (most recent call last):
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 477, in _decrypt_signature
    return func(s)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 450, in <lambda>
    return lambda s: initial_function([s])
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 148, in resf
    res = self.interpret_statement(stmt, local_vars)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 44, in interpret_statement
    'Cannot determine left side of statement in %r' % stmt)
youtube_dl.utils.ExtractorError: Cannot determine left side of statement in 'Go.sH(a,2)'; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.
; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.
Traceback (most recent call last):
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 477, in _decrypt_signature
    return func(s)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 450, in <lambda>
    return lambda s: initial_function([s])
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 148, in resf
    res = self.interpret_statement(stmt, local_vars)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 44, in interpret_statement
    'Cannot determine left side of statement in %r' % stmt)
youtube_dl.utils.ExtractorError: Cannot determine left side of statement in 'Go.sH(a,2)'; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.
Traceback (most recent call last):
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 477, in _decrypt_signature
    return func(s)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 450, in <lambda>
    return lambda s: initial_function([s])
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 148, in resf
    res = self.interpret_statement(stmt, local_vars)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 44, in interpret_statement
    'Cannot determine left side of statement in %r' % stmt)
youtube_dl.utils.ExtractorError: Cannot determine left side of statement in 'Go.sH(a,2)'; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib64/python3.3/site-packages/youtube_dl/YoutubeDL.py", line 516, in extract_info
    ie_result = ie.extract(url)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/common.py", line 169, in extract
    return self._real_extract(url)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 847, in _real_extract
    encrypted_sig, video_id, player_url, age_gate)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 481, in _decrypt_signature
    u'Automatic signature extraction failed: ' + tb, cause=e)
youtube_dl.utils.ExtractorError: Automatic signature extraction failed: Traceback (most recent call last):
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 477, in _decrypt_signature
    return func(s)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/extractor/youtube.py", line 450, in <lambda>
    return lambda s: initial_function([s])
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 148, in resf
    res = self.interpret_statement(stmt, local_vars)
  File "/usr/lib64/python3.3/site-packages/youtube_dl/jsinterp.py", line 44, in interpret_statement
    'Cannot determine left side of statement in %r' % stmt)
youtube_dl.utils.ExtractorError: Cannot determine left side of statement in 'Go.sH(a,2)'; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.
; please report this issue on https://yt-dl.org/bug . Be sure to call youtube-dl with the --verbose flag and include its complete output. Make sure you are using the latest version; type  youtube-dl -U  to update.

[phihag]

You are using an outdated version of youtube-dl. YouTube changed their player on 2014-07-25, so you'll need at least youtube-dl version 2014.07.25 (or newer).

It looks like you installed youtube-dl with a package manager (something like emerge, or pip). You can use that package manager to update youtube-dl (you may need to contact the package maintainer though, and request an update).

Alternatively, uninstall the youtube package and follow our manual installation instructions. From then on, you'll be able to update with sudo youtube-dl -U.