- pause:
    prompt: |
      Choose the Desktop you want to install: 
      0: Don't install any Desktop
      1: GNOME
      2: KDE
      3: Xfce
      4: Mate     
      private: no
      Default:0
  register: os_desktop_options

- set_fact:
    os_desktop_meta:
      "0": ""
      "1": "gnome"
      "2": "kde"
      "3": "xfce"
      "4": "mate"
      
- set_fact:
    os_desktop: "{{os_desktop_meta[os_desktop_options.user_input]}}"

- debug:
    msg: "Now start to install os_desktop is {{os_desktop}}"