Solving “insecure string pickle” in youtube-dl

I am trying to use youtube-dl to download something for my missus, and the error “insecure string pickle” issue is preventing the video being downloaded. After a few hours of searching the internet finally the following blog solved my problem.

The solution is quite simple:

brew install libav ffmpeg rtmpdump

Just to note my system is Hackintosh running el-capitan with homebrew installed.