Create shutdown button on left menu on ubuntu

1. vim ~/.local/share/applications/shutdown.desktop
2. Insert text

[Desktop Entry]
 Categories=Application;System;
 Comment=To shutdown the computer
 Encoding=UTF-8
 Exec=gnome-session-quit --power-off
 Icon=system-shutdown
 Name=Shutdown-Button
 NoDisplay=false
 StartupNotify=false
 Terminal=false
 Type=Application

3. save
4. type shutdown and drage to menu