Decrypt blockstack encryptedPortalKey

decrypt.js

var triplesec = require('triplesec');

var encryptedPortalKey = new Buffer("<encryptedPortalKey>", "hex");
var password = new Buffer("<password>");

triplesec.decrypt({key: password, data: encryptedPortalKey}, function(err, plaintext) {
    if (err) {
        console.log(err);
    } else {
        console.log("Your backup phrase:");
        console.log(plaintext.toString());
    }
});