Python 3.4.3中的NameError

Python 3.4.3中的NameError,python,beautifulsoup,syntax-error,Python,Beautifulsoup,Syntax Error,当我使用以下配置尝试此操作时: 带python3.4.3的VirtualEnv 在在线IDE上运行 当我尝试这个时: from urllib.request import urlopen from urllib.error import HTTPError from bs4 import BeautifulSoup try: html = urlopen("http://www.pythonscraping.com/pages/pages1.html") if html is No

当我使用以下配置尝试此操作时:

  • 带python3.4.3的VirtualEnv
  • 在在线IDE上运行
当我尝试这个时:

from urllib.request import urlopen
from urllib.error import HTTPError
from bs4 import BeautifulSoup
try:
    html = urlopen("http://www.pythonscraping.com/pages/pages1.html")

if html is None:
        print("url not found")
else:
    except HTTPError as e:
        print("test")
    else:
        bsObj = BeautifulSoup(html.read())
        print(bsObj)
我得到了以下错误:

~/workspace/scrapingEnv $ python test2.py
  File "test2.py", line 7
    if html is None:
     ^
SyntaxError: invalid syntax

我做错了什么?

谢谢你的提示,我找到了解决问题的方法:

from urllib.request import urlopen
from urllib.error import HTTPError
from urllib.error import URLError
from bs4 import BeautifulSoup

try:
    html = urlopen("http://www.pythonscrapng.com/pages/pages1.html")
    bsObj = BeautifulSoup(html.read())
    print(bsObj)

except HTTPError as e:
    print("test")
except URLError as j:
    print ("No URL")
else:
    bsObj = BeautifulSoup(html.read())
    print(bsObj)

除了和如果/
如果
/
否则
嵌套得很奇怪,缩进在Python中很重要,如果缩进是文件格式的准确表示,则它在Python中无效。