pyoptical: 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/bin/pyoptical - from package: python-pyoptical

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

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