Ultra(초음파) Python

# -*- coding: utf-8 -*-
import RPi.GPIO as gpio
import time

TRIGER = 12 #초음파 tring
ECHO = 16   #초음파 echo


# ____gipo 핀 세팅___#
gpio.cleanup()
gpio.setmode(gpio.BCM)
gpio.setup(TRIGER, gpio.OUT)
gpio.setup(ECHO,gpio.IN)

#초음파 함수
def Ultra():
    global cnt_One, cnt_Tree, cnt_Two, dist1
    while True:
        gpio.output(TRIGER,gpio.LOW)
        time.sleep(0.1)
        gpio.output(TRIGER,gpio.HIGH)
        time.sleep(0.00002)
        gpio.output(TRIGER,gpio.LOW)
        
        while gpio.input(ECHO) == gpio.LOW:
            startTime = time.time()
            
        while gpio.input(ECHO) == gpio.HIGH:
            endTime = time.time()
          
        period = endTime - startTime
        dist1 = round(period * 1000000 / 58, 2)
        
        print('Dist1', dist1, 'cm')
        
 Ultra()