[Question] common _search_regex function always throws exception

[Wandang]

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Description of your issue, suggested solution and other information

I am having trouble with common.py's _search_regex function.
Based on the description I can give it a pattern/regex, a string to search through and a code word for logging that is free to chose.

Furthermore it states that it takes the first matching group to work with. I just can't get this to work.
I've gone so far to blatantly search for a fixed url in the webpage: https://regex101.com/r/33L08o/1

The webpage is http://www.vol.at/blue-man-group/5593454

As you can see in the regex101.com link the first group that is detected is the url. But I still get an RegexNotFoundError/Exception.

My code:

        video_id = self._match_id(url)
        webpage = self._download_webpage(url, video_id)
        title =  self._og_search_title(webpage)
        print("regex test")
        video_url = self._search_regex(
            r'(?s)file:\s*"(https://vs-pd-russmedia\.sf\.apa\.at/vs_vn/20171215_20_169570_bluemangroupe_720\.mp4\?guid=293f6d17-692a-44e3-9fd5-7b178f3a1029)"',
            webpage, 'url')

[dstftw]

There is no code matching this regex at http://www.vol.at/blue-man-group/5593454 thus you are getting RegexNotFoundError.