Python 3.x RPi上的Python 3瓶子int（）的文本无效，基数为10:'；favicon.ico'；

我最近买了一本覆盆子皮和一本书（覆盆子皮食谱）。其中一个项目是通过网页控制RPi上的GPIO引脚。当我在输入代码后第一次运行代码时，我收到了一系列错误，因此，我尝试运行books github页面上列出的代码：

from bottle import route, run
import RPi.GPIO as GPIO

host = '192.168.1.8'

GPIO.setmode(GPIO.BCM)
led_pins = [18, 23, 24]
led_states = [0, 0, 0]
switch_pin = 25

GPIO.setup(led_pins[0], GPIO.OUT)
GPIO.setup(led_pins[1], GPIO.OUT)
GPIO.setup(led_pins[2], GPIO.OUT)
GPIO.setup(switch_pin, GPIO.IN, pull_up_down=GPIO.PUD_UP)

def switch_status():
    state = GPIO.input(switch_pin)
    if state:
        return 'Up'
    else:
        return 'Down'

def html_for_led(led):
    l = str(led)
    result = " <input type='button' onClick='changed(" + l + ")' value='LED " + l + "'/>"
    return result

def update_leds():
    for i, value in enumerate(led_states):
        GPIO.output(led_pins[i], value)

@route('/')
@route('/<led>')
def index(led="n"):
    print(led)
    if led != "n":
        led_num = int(led)
        led_states[led_num] = not led_states[led_num]
        update_leds()
    response = "<script>"
    response += "function changed(led)"
    response += "{"
    response += "  window.location.href='/' + led"
    response += "}"
    response += "</script>"

    response += '<h1>GPIO Control</h1>'
    response += '<h2>Button=' + switch_status() + '</h2>'
    response += '<h2>LEDs</h2>'
    response += html_for_led(0) 
    response += html_for_led(1) 
    response += html_for_led(2) 
    return response

run(host=host, port=80)

知道这是怎么回事吗？非常感谢您的帮助。

您的建议是什么

print led

表演

他们说led不是整数，所以错误可能来自那里

print led