python之Selenium:列表索引超出范围错误

我得到了

Traceback (most recent call last): 
  File "<stdin>", line 2, in <module> 
IndexError: list index out of range 

每当我尝试运行此代码时出错。我只是想打印此页面上的所有 URL。有人可以告诉我，我做错了什么吗？？

from selenium import webdriver 
browser = webdriver.Firefox() 
browser.get("http://www.tour-india.net/best-of-india.htm") 
cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
for i in range(0,len(cities)): 
    cities1=browser.find_elements_by_css_selector(".posts1>a>h2")[i] 
    cities1.click() 
    title=browser.find_elements_by_xpath("//title") 
    content=browser.find_elements_by_css_selector(".tours_text_innerpage.content_margin_top") 
    currentUrl=browser.current_url 
    print currentUrl 
    browser.back() 

编辑: 我正在对代码进行一些修改 我在 for 循环之后再次添加了 cities=browser.find_elements_by_css_selector(".posts1>a>h2") ，突然索引错误停止了。现在我很困惑为什么会这样。？？

from selenium import webdriver 
browser = webdriver.Firefox() 
browser.get("http://www.tour-india.net/best-of-india.htm") 
cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
for i in range(0,len(cities)): 
    cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
    cities1=browser.find_elements_by_css_selector(".posts1>a>h2")[i] 
    cities1.click() 
    title=browser.find_elements_by_xpath("//title") 
    content=browser.find_elements_by_css_selector(".tours_text_innerpage.content_margin_top") 
    currentUrl=browser.current_url 
    print currentUrl 
    browser.back() 

编辑:我的整个回溯

>>> import traceback 
>>> from selenium import webdriver 
>>> browser = webdriver.Firefox() 
>>> browser.get("http://www.tour-india.net/best-of-india.htm") 
>>> cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
>>> for i in range(0,len(cities)):       
...     try: 
...             #cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
...             cities1=browser.find_elements_by_css_selector(".posts1>a>h2")[i] 
...             cities1.click() 
...             title=browser.find_elements_by_xpath("//title") 
...             content=browser.find_elements_by_css_selector(".tours_text_innerpage.content_margin_top") 
...             currentUrl=browser.current_url 
...             print currentUrl 
...             browser.back() 
...     except: 
...             print traceback.format_exc() 
...  
http://www.tour-india.net/golden-triangle.htm 
http://www.tour-india.net/golden-triangle-varanasi.htm 
http://www.tour-india.net/magnificent-rajasthan.htm 
http://www.tour-india.net/northindia-rajasthan-tour.htm 
http://www.tour-india.net/north_india_himalaya_tour.htm 
Traceback (most recent call last): 
  File "<stdin>", line 4, in <module> 
IndexError: list index out of range 
 
http://www.tour-india.net/southindia-panorma.htm 
http://www.tour-india.net/classical-rajasthan-tours.htm 
http://www.tour-india.net/rajasthan-forts.htm 
http://www.tour-india.net/india-nepal-tour.htm 
http://www.tour-india.net/southindia-glimpses.htm 
http://www.tour-india.net/enchanting-southindia.htm 
http://www.tour-india.net/shekhawati-tours.htm 
http://www.tour-india.net/delhi-tour.htm 
http://www.tour-india.net/bombay-goa.htm 
http://www.tour-india.net/royal-rajasthan.htm 
http://www.tour-india.net/grand-mughal.htm 
http://www.tour-india.net/north_india_himalaya_tour.htm 
http://www.tour-india.net/northindia-images.htm 
http://www.tour-india.net/karnataka-heritage.htm 
http://www.tour-india.net/leh-ladakh.htm 
Traceback (most recent call last): 
  File "<stdin>", line 4, in <module> 
IndexError: list index out of range 
 
http://www.tour-india.net/darjeeling-sikkim.htm 
http://www.tour-india.net/himalayan-heritage.htm 
Traceback (most recent call last): 
  File "<stdin>", line 4, in <module> 
IndexError: list index out of range 
 
http://www.tour-india.net/rajasthan-goa.htm 
http://www.tour-india.net/rajasthan-forts-palaces.htm 
http://www.tour-india.net/rajasthan-mp.htm 
http://www.tour-india.net/rajasthan-nepal.htm 
http://www.tour-india.net/splendid-gujarat.htm 

请您参考如下方法:

在 cities 解决问题后再次调用 cities 变量。我仍然不知道为什么。但它工作正常。因为没有人发布答案。接受我自己的回答

from selenium import webdriver 
browser = webdriver.Firefox() 
browser.get("http://www.tour-india.net/best-of-india.htm") 
cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
for i in range(0,len(cities)): 
    cities=browser.find_elements_by_css_selector(".posts1>a>h2") 
    cities1=browser.find_elements_by_css_selector(".posts1>a>h2")[i] 
    cities1.click() 
    title=browser.find_elements_by_xpath("//title") 
    content=browser.find_elements_by_css_selector(".tours_text_innerpage.content_margin_top") 
    currentUrl=browser.current_url 
    print currentUrl 
    browser.back(