youku.com broken site

[zhengfan2014]

Checklist

• I'm reporting a broken site support
• I've verified that I'm running youtube-dl version 2020.03.24
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that all URLs and arguments with special characters are properly quoted or escaped
• I've searched the bugtracker for similar issues including closed ones

Verbose log

[youku] XNDU4OTM3NzM0NA: Retrieving cna info
[youku] XNDU4OTM3NzM0NA: Downloading JSON metadata
ERROR: XNDU4OTM3NzM0NA: Failed to parse JSON  (caused by JSONDecodeError('Expecting value: line 1 column 1 (char 0)',)); 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.

Description

Hello, I run ytdl error in google colab test environment, this is my google colab test environment address:
link