from machine import ADC
from machine import Pin
import utime
ldr_value = ADC(28)
relay = Pin(2, Pin.OUT)
while True:
  I=ldr_value.read_u16()
  print(I)
  if I>18020:
   relay.value(1)
  else:
   relay.value(0)
  utime.sleep(0.1)