import utime
from machine import Pin, PWM
utime.sleep(0.1) # Wait for USB to become ready

servo = PWM(Pin(0))
servo.freq(50)

MIN_DUTY = int((1 / 20) * 65535)  # 3277 (1ms pulse)
MAX_DUTY = int((2 / 20) * 65535)  # 6554 (2ms pulse)

while True:
    servo.duty_u16(MIN_DUTY)
    utime.sleep(1)
    servo.duty_u16(MAX_DUTY)
    utime.sleep(1)