Applescript editor not responding

I did the following script in order to identify itunes songs that doesn't have artwork. It's based on other script that I found in net.

tell application "iTunes"
    repeat with a in every track of playlist "Library"
       if not (exists (artwork 1 of a)) then
          add (get location of a) to (playlist "noart")
       end if
    end repeat
 end tell
 

It seems to be working, it compiles well, and because I can that it in event log windows:

tell application "iTunes"
     count every track of playlist "Library"
         --> 10684
     exists artwork 1 of item 1 of every track of playlist "Library"
         --> true
     exists artwork 1 of item 2 of every track of playlist "Library"
         --> true
 

But after 4 hundred tracks, it starts to run slowly, and applescript stops responding after one thousand tracks.

I thought that maybe I could be exhausting my mac memory, but in Activity Monitor, I can see that Applescript is consuming 100% CPU and less than 50MB of memory. I'm running macos 10.7.4 on a macbook pro (i7 with 4GB ram).

As you can see my itunes library has 10684 tracks. It's not a small library, but it's not a huge one.

Does anyone has any advice? Or a script to identify tracks without artwork?

TIA,

Bob

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