Plot MIDI in Python with pretty_midi and pyplot

plot_midi.py

import pretty_midi as pm
from itertools import cycle
import matplotlib.pyplot as plt
import matplotlib.patches as patches


def plot_midi(midi: pm.PrettyMIDI):
    fig, ax = plt.subplots()
    colors = plt.rcParams['axes.prop_cycle'].by_key()['color']
    colors = cycle(colors)

    for instrument in midi.instruments:
        color = next(colors)
        for note in instrument.notes:
            rectangle = patches.Rectangle(
                [note.start, note.pitch],
                note.end - note.start, 1,
                facecolor=color
            )
            ax.add_patch(rectangle)
            rectangle = patches.Rectangle(
                [note.start, note.pitch],
                0.05, 1,
                facecolor='#0004',
            )
            ax.add_patch(rectangle)
    ax.plot()