dh_pydeb: command not found

Have You tried accessing the binary with the full path?

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/dh_pydeb - from package: python-van.pydeb

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