epydocgui: 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/epydocgui - from package: epydoc

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

On Debian possible default full paths are:

/usr/bin/epydocgui - from package: python-epydoc

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

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