from machine import Pin
from utime import sleep

led = Pin(5, Pin.OUT)
switch = Pin(6, Pin.IN, Pin.PULL_UP)

while True:
    while switch.value():  
        pass

    for minute in range(3, 0, -1):  
        for _ in range(minute * 5 * 2):  
            led.high()  
            sleep(0.5)
            led.low()   
            sleep(0.5)
        if minute > 0:
            sleep(60 - (minute * 5 * 2) * 1.0)  

    while not switch.value(): 
        pass