pycode-browser-book: 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/pycode-browser-book - from package: pycode-browser

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

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