it('Parse HASH128_MAX', function() {
   var val = 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF';
   var so = new SerializedObject(val);
   var num = types.Hash128.parse(so);
   assert.strictEqual(num.to_hex(), val);
 });
 it('Serialize 102030405060708090A0B0C0D0E0F000', function() {
   var so = new SerializedObject();
   types.Hash128.serialize(so, '102030405060708090A0B0C0D0E0F000');
   assert.strictEqual(so.to_hex(), '102030405060708090A0B0C0D0E0F000');
 });
 it('Serialize HASH128_MAX', function() {
   var so = new SerializedObject();
   types.Hash128.serialize(so, 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF');
   assert.strictEqual(so.to_hex(), 'FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF');
 });
 it('Serialize 0', function() {
   var so = new SerializedObject();
   types.Hash128.serialize(so, '00000000000000000000000000000000');
   assert.strictEqual(so.to_hex(), '00000000000000000000000000000000');
 });