from picozero import Servo  
from time import sleep

# creating a Servo object
servo = Servo(15)
LED = machine.Pin(21,machine.Pin.OUT)
# continuously swing the servo arm to min, mid, and max positions (for a duration of 1 sec each)
while True:
    LED.value(0)
    # swinging the servo arm to its min position
    servo.min()
    sleep(3)
    LED.value(1)
    # swinging the servo arm to its max position
    servo.max()
    sleep(3)