Use this to download this category as MP3 with youtube-dl:
declare -a list=("https://www.youtube.com/channel/UCnBN5dTNTyU3nZ2N14Y4z8A/videos" "https://www.youtube.com/c/SaveAFox/videos" "https://www.youtube.com/c/zefrank/videos" "https://www.youtube.com/channel/UC_g32e3JeECjEuRbk-loywg/" "https://www.youtube.com/user/AntsCanada/videos" "https://www.youtube.com/user/NatGeoWild/videos" "https://www.youtube.com/user/Aleiaanimallover368/videos" "https://www.youtube.com/channel/UCmNbW4koY12-duBCFThChGg")
for val in ${list[@]}; do
name=$(basename "$val")
if [ -e $name ]
then
continue
fi
mkdir $name
cd $name
youtube-dl -f mp3-128 $val
cd ..
done
