pysnmptrap: 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/pysnmptrap - from package: python-pysnmp4-apps

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