content: use AppleScript version "2.4" -- Yosemite (10.10) or later
  use scripting additions
  
  on toggleiTunesVolume(minVolume, maxVolume)
  	tell application "iTunes"
  		set current_volume to sound volume
  		if current_volume > minVolume then
  			set desired_volume to minVolume
  		else
  			set desired_volume to maxVolume
  		end if
  		set sound volume to desired_volume
  	end tell
  end toggleiTunesVolume
  
  on setiTunesVolume(desiredVolume)
  	tell application "iTunes"
  		set sound volume to desiredVolume
  	end tell
  end setiTunesVolume