Randomly choose color for shape

Question

I am working on a project for fun in which I need to have 144 squares choose a random color out of a pool (array) of predetermined colors and I need these shapes to do so every 1 second in the project. I was thinking the only way would be to write an after effects script, but I also thought it'll be cool if I could per object place a script which I do not know if it's possible.
The only thing I am familiar with in after effects is creating time lapse. I have not played with it much more than that, however I am familiar with coding and have written some advanced scripts for Photoshop.
Any help in pointing me into the right direction will be appreciated.
Thanks

Answer 1

So, played around with what you mentioned, and nether of them will do what I needed. I ended up playing with scripting and finally finished getting what I wanted.
#target aftereffects
var colors = [[1,0.95294117647059,0.4,1],[1,1,0.6,1],[1,0.91764705882353,0.21960784313725,1],[1,1,0.054901960784314,1],[1,0.96470588235294,0.36470588235294,1],[1,0.8156862745098,0.26274509803922,1],[1,0.92156862745098,0.26274509803922,1],[1,0.88235294117647,0.26274509803922,1],[1,0.90980392156863,0.43529411764706,1],[1,0.97254901960784,0.49803921568627,1]];
app.beginUndoGroup("Color Change");
var comp1 = app.project.item(1); //Comp 1
var duration = comp1.workAreaDuration;
var squares = comp1.layer(2).property("ADBE Root Vectors Group"); //Squares
for (var i=1; i<=squares.numProperties; i++) {
    var square = squares.property(i);
    var fillColor = square.property("ADBE Vectors Group").property("ADBE Vector Graphic - Fill").property("ADBE Vector Fill Color");
    while (fillColor.numKeys!=0) {
        fillColor.removeKey(1);
    var previousColor = 0;
    for (var t=0; t<duration; t+=0.5) {
        var choosenColor  = 0;
        while (true) {
            var choosenColor = Math.floor(Math.random()*colors.length);
            if (t==0 || choosenColor!=previousColor) {
                break;
        previousColor = choosenColor;
        var color = colors[choosenColor];
        fillColor.setValueAtTime(t, color);
    for (var k=1; k<=fillColor.numKeys; k++) {
        fillColor.setInterpolationTypeAtKey(k, KeyframeInterpolationType.HOLD, KeyframeInterpolationType.HOLD);
app.endUndoGroup();