from machine import pin, time_pulse_us
import time

#Pin setup
trigger = Pin(4, Pin .OUT)
echo =Pin(5, Pin.IN)


# Function to measure distance 
def get_distance():
trigger.low()
time.sleep_us(2)
trigger.high()
time.sleep_us(10)
trigger.low()


duration= time.time_pulse(echo, 1, 30000)
if duration  < 0:
  return none


 distance = duration/ 58.0
 return distance

 while True:
 distance = get_()
 if distance is not none:
 # print to screen
 print('Distance:  {:.2f} cm '.format(distance))