youtube-dlでUnable to download webpage: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failedエラーが発生した場合の対処です。

WARNING: Could not send HEAD request to https://www.nicovide.jp/watch/sm25733270: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:590)>
[generic] sm25733270: Downloading webpage
ERROR: Unable to download webpage: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:590)> (caused by URLError(SSLError(1, u'[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:590)'),))

--no-check-certificateオプションをつける。

SSL certificate verify failed · Issue #4816 · ytdl-org/youtube-dl