doit: 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/doit - from package: python-doit

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