background.py: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/share/games/oneisenough/bin/background.py - from package: oneisenough

You may install the required package with command apt-get install {package}

Error in other languages:
background.py: bevel nie gevind nie
background.py: comandă negăsită
background.py: comando não encontrado
background.py: commande introuvable
background.py: command not found
background.py: käsku ei ole
background.py: không tìm thấy lệnh
background.py: komanda nerasta
background.py: Kommando nicht gefunden.
background.py: kommandot finns inte
background.py: komut yok
background.py: nie znaleziono polecenia
background.py: níor aimsíodh an t-ordú
background.py: no se encontró la orden
background.py: no s'ha trobat l'ordre
background.py: opdracht niet gevonden
background.py: parancs nem található
background.py: perintah tidak ditemukan
background.py: príkaz nenájdený
background.py: příkaz nenalezen
background.py: команда не найдена
background.py: командата не е открита
background.py: 命令找不到
background.py: コマンドが見つかりません