2to3: 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/2to3 - from package: python-tools

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

On Debian possible default full paths are:

/usr/bin/2to3 - from package: python

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

Error in other languages:
2to3: bevel nie gevind nie
2to3: comandă negăsită
2to3: comando não encontrado
2to3: commande introuvable
2to3: command not found
2to3: käsku ei ole
2to3: không tìm thấy lệnh
2to3: komanda nerasta
2to3: Kommando nicht gefunden.
2to3: kommandot finns inte
2to3: komut yok
2to3: nie znaleziono polecenia
2to3: níor aimsíodh an t-ordú
2to3: no se encontró la orden
2to3: no s'ha trobat l'ordre
2to3: opdracht niet gevonden
2to3: parancs nem található
2to3: perintah tidak ditemukan
2to3: príkaz nenájdený
2to3: příkaz nenalezen
2to3: команда не найдена
2to3: командата не е открита
2to3: 命令找不到
2to3: コマンドが見つかりません