Play announcement on a group of speakers

I have the following and want to know how to properly play announcement on multiple speakers.

https://paste.ubuntu.com/p/BbBtFnH9m5/

I have the following group

garage_alerts:
  name: Garage_Alert_Devices
  entities:
    - media_player.great_room
    - media_player.master_bathroom
    - media_player.mike_s_echo_dot
    - media_player.office

and I want to play the following announcement script to the group

notificationgaragedoor:
  alias: 'Garage Door Open'
  sequence:
    - service: script.sonos_say
      data:
        sonos_entity: media_player.great_room
        volume: 0.35
        delay: '00:00:02'
        message: 'Garage door is open, please check!'

How do I play the announcement to the group and not just the one sonos_entity?

I was able to solve this.

How did you solve it?

by using a group with the appropriate devices. group.sonos_devices