Cannot get label color from script

I want to use Extend script to get the color of the labels of the clips in a Premiere pro sequence.
However, I keep getting “undefined”.
The clips in the sequence are labeled with various colors as shown in the image.
I have looked in various explanatory articles, but I could not find the answer.
If you could tell me how to do this, I would appreciate it.

What the Console Displays↓

3 undefined 4

var project = app.project ; var sequence = project.activeSequence ; 
$ .writeln ( sequence.videoTracks.numTracks ) ; 
$ .writeln ( sequence.videoTracks [ 0 ] .clips [ 0 ] .labels ) ; $ .writeln ( sequence.audioTracks.numTracks ) ;​​​​​
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