import machine
from machine import Pin, PWM
import utime, math
from time import sleep
# pwm
pwm = PWM(Pin(2), freq=50, duty=20)
def Servo(servo, angle):
    pwm.duty(int(((angle)/180 *2 + 0.5) / 20 * 1023))    
while True:
    Servo(2,180)
    sleep(1)
    Servo(2,90)
    sleep(1)
    Servo(2,0)
    sleep(1)