Downloading a pdf based webpage as pdf using Python

Here is given a method to download a webpage as pdf, which works.

However, the website I am interested in is also displaying a pdf itself, so this method does not work. For example, this page. Is there anything specific for such url's?

When I use the post I shared above, I get the following error:

OSError: wkhtmltopdf reported an error:
Loading pages (1/6)
Error: Failed loading page http://curia.europa.eu/juris/showPdf.jsf;jsessionid=CAE85693A88870E357F61ED4344FD7E9?text=&docid=62809&pageIndex=0&doclang=EN&mode=lst&dir=&occ=first&part=1&cid=2878455 (sometimes it will work just to ignore this error with --load-error-handling ignore)
Exit with code 1, due to unknown error.