pypyclean: 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/pypyclean - from package: pypy

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

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