gnatpython-opt-parser: 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/gnatpython-opt-parser - from package: python-gnatpython

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

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