on right click holding a feather:
    name of held item contains "§aDoubleJump"
    if {%player%.doublejump} is not set:
        push player upwards at speed 1.2
        execute console command "execute %player% ~ ~ ~ /particle lava ~ ~ ~ 0.1 0 0.1 0.2 20"
        execute console command "execute %player% ~ ~ ~ /particle flame ~ ~ ~ 0.1 0 0.1 0.1 20"
        execute console command "execute %player% ~ ~ ~ /playsound minecraft:block.lava.extinguish master @a ~ ~ ~"
        set {%player%.doublejump} to "cannot"
        set {%player%.cooltime} to 20
        wait 1 seconds
        set {%player%.cooltime} to 19
        wait 1 seconds
        set {%player%.cooltime} to 18
        wait 1 seconds
        set {%player%.cooltime} to 17
        wait 1 seconds
        set {%player%.cooltime} to 16
        wait 1 seconds
        set {%player%.cooltime} to 15
        wait 1 seconds
        set {%player%.cooltime} to 14
        wait 1 seconds
        set {%player%.cooltime} to 13
        wait 1 seconds
        set {%player%.cooltime} to 12
        wait 1 seconds
        set {%player%.cooltime} to 11
        wait 1 seconds
        set {%player%.cooltime} to 10
        wait 1 seconds
        set {%player%.cooltime} to 9
        wait 1 seconds
        set {%player%.cooltime} to 8
        wait 1 seconds
        set {%player%.cooltime} to 7
        wait 1 seconds
        set {%player%.cooltime} to 6
        wait 1 seconds
        set {%player%.cooltime} to 5
        wait 1 seconds
        set {%player%.cooltime} to 4
        wait 1 seconds
        set {%player%.cooltime} to 3
        wait 1 seconds
        set {%player%.cooltime} to 2
        wait 1 seconds
        set {%player%.cooltime} to 1
        wait 1 seconds
        delete {%player%.cooltime}
        delete {%player%.doublejump}
        send "&a[DoubleJump] &e２段ジャンプを使用できるようになりました！"
    else:
        send "&a[DoubleJump] &c２段ジャンプを使用するには &a%{%player%.cooltime}%秒 &c待たなければいけません！"