dh_pysupport: 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

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_pysupport - from package: python-support

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