使用selenium python在phptravels站点测试dropdown时，我遇到了issue.that，我无法从dropdown中选择值

from selenium.webdriver.support.ui import Select

dropdown_element = driver.find_element_by_id("dropdown_id")
dropdown = Select(dropdown_element)

dropdown.select_by_index(index)

dropdown.select_by_visible_text("option_text")

dropdown.select_by_value("option_value")

from selenium import webdriver
from selenium.webdriver.support.ui import Select

# 启动浏览器
driver = webdriver.Chrome()

# 打开phptravels网站
driver.get("https://www.phptravels.net/")

# 找到下拉菜单的元素并选择值
dropdown_element = driver.find_element_by_name("dropdown_name")
dropdown = Select(dropdown_element)
dropdown.select_by_visible_text("option_text")

# 关闭浏览器
driver.quit()