Whats this fool done- alternative to variety

I find Variety a little heavy on system resounces so uninstalled it.
In other distros lint mint debian I was using this script to change the wallpaper. What changes would I need to make for it to work on PinGuyOs?

# Script to randomly set Background from files in a directory
while true;do

# Directory Containing Pictures
DIR="/media/user/IomegaHDD/MyWallpapers"

# Command to Select a random jpg file from directory
# Delete the *.jpg to select any file but it may return a folder
PIC=$(ls $DIR/*.* | shuf -n1)

# Command to set Background Image
gsettings set org.mate.background picture-filename $PIC

# specify how long to wait in seconds between changes
sleep 1000

done