import machine
from machine import Pin,PWM
from time import sleep_us,sleep
import machine
from machine import Pin, PWM
import utime, math
from time import sleep
# pwm
pwm = PWM(Pin(16), freq=50, duty=0)
def Servo(servo, angle):
    pwm.duty(int(((angle)/180 * 2 + 0.5) / 20 * 1023))
echo = Pin(13,Pin.IN)
trig = Pin(12,Pin.OUT)
led = Pin(14,Pin.OUT)
while True :
    trig.value(0)
    sleep_us(2)
    trig.value(1)
    sleep_us(10)
    trig.value(0)
    x = machine.time_pulse_us(echo,1)
    distance = (0.034*x)/2
    print('distance', distance, 'D' )
    if distance <40 :
        Servo(16,120)
        led.on()
        sleep(1)
    else :
        distance >40 
        Servo(16,0)
        led.off()
        sleep(1)