Fotoresistencia y foco

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from turtle import *
import turtle 
import numpy as np
from pylab import*
import random
import time
import RPi.GPIO as GPIO, time
t=Turtle()
screen=t.getscreen()
setup(400,300,0,0)
screensize(150,150)
colormode(255)
t=Turtle()
t.speed(10)
screen=t.getscreen()
setup(900,620,0,0)
screensize(500,150)
colormode(255)
turtle.bgcolor("darkgray")
t.hideturtle()
t.penup()
t.pensize(5)
t.goto(-250,-150)
t.pendown()
t.goto(450,-150)
t.penup()
t.goto(-250,-150)
t.pendown()
t.goto(-450,-300)
t.penup()
t.goto(-250,-150)
t.pendown()
t.goto(-250,500)
t.penup()
t.goto(100,300)
t.pendown()
t.dot(40,255,255,255)
t.dot(40,255,250,0)
t.bgcolor("darkgray")
GPIO.setmode(GPIO.BCM)
valor=0

def medida ():
measurement = 0
while (GPIO.input(4) == GPIO.LOW):
measurement += 1
print(measurement)
return(measurement)


while True:
GPIO.setup(4, GPIO.OUT)
GPIO.output(4, GPIO.LOW)
time.sleep(0.1)
GPIO.setup(4, GPIO.IN)
valor=medida()
if valor > 0 and valor < 40:
t.dot(40,255,250,0)
elif valor > 40 and valor < 80:
t.dot(40,255,250,14)
elif valor > 80 and valor < 160:
t.dot(40,255,250,28)
elif valor > 160 and valor < 200:
t.dot(40,255,250,42)
elif valor > 200 and valor < 240:
t.dot(40,255,250,56)
elif valor > 240 and valor < 280:
t.dot(40,255,250,70)
elif valor > 280 and valor < 320:
t.dot(40,255,250,84)
elif valor > 320 and valor < 360:
t.dot(40,255,250,98)
elif valor > 360 and valor < 400:
t.dot(40,255,250,112)
elif valor > 400 and valor < 440:
t.dot(40,255,250,126)
elif valor > 440 and valor < 480:
t.dot(40,255,250,140)
elif valor > 480 and valor < 520:
t.dot(40,255,250,154)
elif valor > 520 and valor < 560:
t.dot(40,255,250,168)
elif valor > 560 and valor < 600:
t.dot(40,255,250,182)
elif valor > 640 and valor < 680:
t.dot(40,255,250,196)
elif valor > 680 and valor < 720:
t.dot(40,255,250,210)
elif valor > 720 and valor < 760:
t.dot(40,255,250,224)
else:
t.dot(40,255,255,255)
exitonclick()

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