popanal.py: 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/share/doc/popularity-contest/examples/bin/popanal.py - from package: popularity-contest

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

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