mutagen-inspect: 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/mutagen-inspect - from package: python-mutagen

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

On Debian possible default full paths are:

/usr/bin/mutagen-inspect - from package: python-mutagen

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

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