gnome-wallpaper-script

Usage:  gnome-wallpaper-script [-h | --help] [-l <ARG>] [-s | --show]
DESCRIPTION
    Download Wallpaper from URLs and Set to the gnome wallpaper.
    OPTIONS:
    -h, --help
        Print this help and exit.
    -s, --show
        Show options for adding.
    -l
        Set line X to the wallpaper.