from machine import Pin
from utime import sleep
ledR=Pin(2,Pin.OUT)
ledY=Pin(7,Pin.OUT)
ledG=Pin(12,Pin.OUT)

while(True):
  ledR.high()
  sleep(10)
  ledR.low()
  
  ledG.high()
  sleep(20)
  ledG.low()

  ledY.high()
  sleep(3)
  ledY.low()