content: 
  on run argv
      set myid to item 1 of argv
      tell application "Keynote"
          set mydoc to document id myid of application "Keynote"
          set myprops to properties of mydoc
          set myfile to file of myprops
          if myfile is missing value
              myfile
          else
              get POSIX path of (file of myprops)
          end if
      end tell
  end run
  