mpipython.openmpi: 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/mpipython.openmpi - from package: openmpipython

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

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