human
2. Extend our music-maker
How can we extend our existing music-maker class to handle instances of our new indicator command? One way to do it is to pass a list of of commands to our music-maker at initialization time. The initializer of the revised music-maker implements a keyword argument to do this. Additionally, we've added a method to our music-maker to call these commands, one after the other in a stack. We've also made our music-maker callable. This means that we'll pass time signatures to our music-maker itself, rather than to any of the music-maker's public methods. And we've prefixed the music-maker's methods with underscores. This indicates that users doesn't need to know anything about these methods:  users initialize a music-maker and then call it. Everything else happens behind the scenes:
assistant
#Here is the Python code you requested.
class MusicMaker:

    def __init__(
        self, 
        counts, 
        denominator, 
        pitches,
        commands=None,
        ):
        self.counts = counts
        self.denominator = denominator
        self.pitches = pitches
        self.commands = commands or ()
        
    def __call__(self, time_signatures):
        """
        Calls music-maker on time signatures.
        """
        time_signatures = [abjad.TimeSignature(_) for _ in time_signatures]
        staff = self._make_notes_and_rests(
            self.counts,
            self.denominator,
            time_signatures,
            )
        self._impose_time_signatures(staff, time_signatures)
        self._pitch_notes(staff, self.pitches)
        self._call_commands(staff)
        return staff

    def _make_notes_and_rests(self, counts, denominator, time_signatures):
        """
        Makes notes and rests.
        """
        durations = [_.duration for _ in time_signatures]
        total_duration = sum(durations)
        talea = rmakers.Talea(counts, denominator)
        talea_index = 0
        leaves = []
        current_duration = abjad.Duration(0)
        while current_duration < total_duration:
            leaf_duration = talea[talea_index]
            if 0 < leaf_duration: 
                pitch = abjad.NamedPitch("c'")
            else:
                pitch = None
                leaf_duration = abs(leaf_duration)
            if total_duration < (leaf_duration + current_duration):
                leaf_duration = total_duration - current_duration
            leaves_ = abjad.LeafMaker()([pitch], [leaf_duration])
            leaves.extend(leaves_)
            current_duration += leaf_duration
            talea_index += 1
        staff = abjad.Staff(leaves)
        return staff

    def _impose_time_signatures(self, staff, time_signatures):
        """
        Imposes time signatures.
        """
        selections = abjad.mutate.split(staff[:], time_signatures, cyclic=True)
        for time_signature, selection in...