gensrv_py.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 CentOS possible default full paths are:

/usr/bin/gensrv_py.py - from package: python-genpy

You may install the required package with command yum install {package}

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