Backpack:
    type: assignment
    actions:
        on assignment:
    interact scripts:
    - 10 BackpackStart

BackpackStart:
    type: world
    events:
        on backpack command:
        - if <player.has_flag[backpack].not> {
        - flag <player> backpack
        - narrate "Congratulations, you executed the backpack command!"
        }