def test_sequence_concat(self):
        s1 = self.make_sequence()
        s2 = self.make_sequence(offset=50)
        concated = s1 + s2
        from sebastian.core import OFFSET_64, MIDI_PITCH, DURATION_64
        self.assertEqual(concated._elements, [
            {MIDI_PITCH: 50, OFFSET_64: 16, DURATION_64: 17},
            {MIDI_PITCH: 53, OFFSET_64: 19, DURATION_64: 20},
            {MIDI_PITCH: 100, OFFSET_64: 105, DURATION_64: 67},
            {MIDI_PITCH: 103, OFFSET_64: 108, DURATION_64: 70}
        ])
serializes the instance to XML
dataset/ETHPy150Open jtauber/sebastian/tests/test_sequences.py/TestSequences.test_sequence_concat--crossover with--dataset/ETHPy150Open marklap/rundeckrun/rundeck/api.py/RundeckNode.serialize