pypi-download: 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/pypi-download - from package: python-stdeb

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