content: 
  tell application "Keynote"
      "{" & ¬
      "\"id\": \"" & id & "\", " & ¬
      "\"name\": \"" & name & "\", " & ¬
      "\"version\": \"" & version & "\", " & ¬
      "\"frozen\": " & frozen & ", " & ¬
      "\"frontmost\": " & frontmost & ", " & ¬
      "\"playing\": " & playing & ", " & ¬
      "\"slide_switcher_visible\": " & slide switcher visible & ¬
      "}"
  end tell
  