[debug] Encodings: locale UTF-8, fs utf-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2018.06.19
[debug] Python version 3.6.4 (CPython) - Darwin-17.5.0-x86_64-i386-64bit
[debug] exe versions: ffmpeg 4.0.1, ffprobe 4.0.1
[debug] Proxy map: {}
ERROR: Unable to download webpage: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:777)> (caused by URLError(SSLError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:777)'),))
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/youtube_dl/extractor/common.py", line 598, in _request_webpage
    return self._downloader.urlopen(url_or_request)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/youtube_dl/YoutubeDL.py", line 2211, in urlopen
    return self._opener.open(req, timeout=self._socket_timeout)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 526, in open
    response = self._open(req, data)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 544, in _open
    '_open', req)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 504, in _call_chain
    result = func(*args)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/youtube_dl/utils.py", line 1101, in https_open
    req, **kwargs)
  File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1320, in do_open
    raise URLError(err)