code: def testToSequenceWithBaseNoteSequence(self):
      poly_seq = polyphony_lib.PolyphonicSequence(
          steps_per_quarter=1, start_step=1
      )
  
      pe = polyphony_lib.PolyphonicEvent
      poly_events = [
          # step 0
          pe(pe.NEW_NOTE, 60),
          pe(pe.NEW_NOTE, 64),
          pe(pe.STEP_END, None),
          # step 1
          pe(pe.CONTINUED_NOTE, 60),
          pe(pe.CONTINUED_NOTE, 64),
          pe(pe.STEP_END, None),
          pe(pe.END, None),
      ]
      for event in poly_events:
          poly_seq.append(event)
  
      base_seq = copy.deepcopy(self.note_sequence)
      testing_lib.add_track_to_sequence(
          base_seq, 0, [(60, 100, 0.0, 1.0)]
      )
  
      poly_seq_ns = poly_seq.to_sequence(
          qpm=60.0, base_note_sequence=base_seq
      )
  
      testing_lib.add_track_to_sequence(
          self.note_sequence,
          0,
          [
              (60, 100, 0.0, 1.0),
              (60, 100, 1.0, 3.0),
              (64, 100, 1.0, 3.0),
          ],
      )
  
      # Make comparison easier
      poly_seq_ns.notes.sort(key=lambda n: (n.start_time, n.pitch))
      self.note_sequence.notes.sort(
          key=lambda n: (n.start_time, n.pitch)
      )
  
      self.assertEqual(self.note_sequence, poly_seq_ns)
  
imports: import copy
  from magenta.common import testing_lib
  from magenta.models.polyphony_rnn import polyphony_lib
  from note_seq import sequences_lib
  from note_seq import testing_lib
  from note_seq.protobuf import music_pb2
  import tensorflow.compat.v1
label_desc: Use image node_id 8 for calling the PolyphonyLibTest obj's underlying member method code with example usage: obj.testToSequenceWithBaseNoteSequence() without return types