Unfortunately, increasingly model providers resort to Google for webspace, which does not allow direct download links. Interactive downloads are nonce-backed and shortlived.
See example.
According to this Stackoverflow entry, they require users to make a second request based on some previous cookie.
This is very annoying, but luckily there is a Python package gdown which can do the dirtywork.
The problem now becomes: how do we integrate this, so other URLs are not affected, and our _download_impl's progress meter and file output still work?