JavaScript Token Generator

function generate_token(length){
    //edit the token allowed characters
    var a = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890".split("");
    var b = [];  
    for (var i=0; i<length; i++) {
        var j = (Math.random() * (a.length-1)).toFixed(0);
        b[i] = a[j];
    }
    return b.join("");
}
generate_token(32); //returns "qweQj4giRJSdMNzB8g1XIa6t3YtRIHPH"
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