import RPi.GPIO as GPIO 
import time 
GPIO.setmode(GPIO.BCM) 
TRIG= pin(15,GPIO.OUT)
ECHO = pin(14,GPIO.IN)
print "Distance Measurement In Progress" 
GPIO.setup(TRIG,GPIO.OUT) 
GPIO.setup(ECHO,GPIO.IN)
GPIO.output(TRIG, False)
print "Waiting For Sensor To Settle" 
time.sleep(2)
GPIO.output(TRIG, True)
time.sleep(0.00001) 
GPIO.output(TRIG, False)
while GPIO.input(ECHO)==0: 
pulse_start = time.time() 
while GPIO.input(ECHO)==1:
pulse_end = time.time()
pulse_duration = pulse_end - pulse_start 
distance = pulse_duration x 17150 
distance = round(distance, 2)
if distance > 2 and distance < 400: 
print "Distance:",distance - 0.5,"cm" 
else: 
print "Out Of Range"
GPIO.cleanup()