Official solution to refactoring challenge from Clean Code on Toilet #1: Naming Things.

sequencer.py

# Sequencer is the music production term of art for what this does
class Sequencer:
    def toggle_record(self, value):
        self.is_recording = value
        if not value:
            for note in self.held_notes.values():
                self.record_midi(midi.NoteOff(note.pitch, note.velocity))
            self.held_notes = {}

    def handle_note(self, note):
        self.engine.send_midi(note)
        if self.is_playing and self.is_recording:
            self.record_midi(note)

    def record_midi(self, note):
        if isinstance(note, midi.NoteOn):
            self.held_notes[note.pitch] = note
        elif isinstance(note, midi.NoteOff):
            self.held_notes.pop(note.pitch)
        # `ticks` is the programming term of art for an int time 
        # (expressed in "frames" of some kind)
        bisect.insort(self.sequence, (self.ticks, note))