import time
time.sleep(0.1) # Wait for USB to become ready
from machine import Pin, PWM
from time import sleep_ms, ticks_ms

button = Pin(14, Pin.IN)
buzzer = PWM(Pin(13))

start_time = ticks_ms()
while True:

    if button.value() ==1:
        timer = 0
        start_time
    elapsed_ms = duration - start_time
    if 880 < elapsed_ms < 1020:
        buzzer.freq(261)
        buzzer.duty_u16(32768)
        sleep_ms(400)
        buzzer.duty_u16(0)
        sleep_ms(100)