pudb: 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/pudb - from package: python-pudb

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

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