Random MIDI piano playing in Python

randpiano.py

import time
import random
import fluidsynth
import futures

fs = fluidsynth.Synth()
fs.start(driver='alsa')

sfid = fs.sfload('piano.sf2')
fs.program_select(0, sfid, 0, 0)

def press(key, velocity=64, duration=0.5):
    fs.noteon(0, key + 19, velocity)
    time.sleep(duration)
    fs.noteoff(0, key + 19)

def random_key(mean_key=44):
    x = random.gauss(mean_key, 10.0)
    if x < 1:
        x = 1
    elif x > 88:
        x = 88
    return int(round(x))

def random_velocity():
    x = random.gauss(100.0, 10.0)
    if x < 1:
        x = 1
    elif x > 127:
        x = 127
    return int(round(x))

def random_duration(mean_duration=2.0):
    x = random.gauss(mean_duration, 2.0)
    if x < 0.2:
        x = 0.2
    return x

def play(mean_key, mean_duration):
    while True:
        key = random_key(mean_key)
        velocity = random_velocity()
        duration = random_duration(mean_duration)
        press(key, velocity, duration)

with futures.ThreadPoolExecutor(max_workers=4) as e:
    e.submit(play, 10, 10.0)
    e.submit(play, 55, 2.0)
    e.submit(play, 55, 2.0)
    e.submit(play, 60, 5.0)

fs.delete()