from machine import Pin
import uasyncio
from utime import sleep

# description of LEDs connected to the board
led1 = Pin(4, Pin.OUT)  # green LED
led2 = Pin(5, Pin.OUT)  # red LED
led3 = Pin(6, Pin.OUT)  # yellow LED

async def blink(led, period):
  while True:
    led.on()
    await uasyncio.sleep(period) # period in s
    led.off()
    await uasyncio.sleep(period)

async def main():
  uasyncio.create_task(blink(led1, 0.16)) # green LED
  uasyncio.create_task(blink(led2, 0.33)) # red LED
  uasyncio.create_task(blink(led3, 0.33)) # orange LED
  # function main() does not contain endless loop
  # if will stop after 10s
  await uasyncio.sleep_ms(10000)

uasyncio.run(main())