python爬虫经常出现的错误提示是什么意思？

[xypcx]

写爬虫的时候经常出现一种错误：Traceback (most recent call last):
File "crawlertest.py", line 3, in
con = urllib2.urlopen(req)
File "C:\python27\lib\urllib2.py", line 154, in urlopen
return opener.open(url, data, timeout)
File "C:\python27\lib\urllib2.py", line 437, in open
response = meth(req, response)
File "C:\python27\lib\urllib2.py", line 550, in http_response
'http', request, response, code, msg, hdrs)
File "C:\python27\lib\urllib2.py", line 475, in error
return self.callchain(*args)
File "C:\python27\lib\urllib2.py", line 409, in callchain
result = func(*args)
File "C:\python27\lib\urllib2.py", line 558, in http_error_default
raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 503: Service Unavailable
原代码如下：
import urllib2
req=urllib2.Request('https://www.amazon.com/')
con = urllib2.urlopen(req)
doc = con.read()
print doc
这种错误提示是什么意思？如何进行改正？

[LinShuiRong]

HTTP Error 503: Service Unavailable

基本的搜索你进行了吗？问之前。

[China_hezt]

缺少headers...

import urllib2

url = 'https://www.amazon.com'
user_agent = 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_5)'
headers = {'User-Agent' : user_agent}
request = urllib2.Request(url,headers = headers)
response = urllib2.urlopen(request)

content = response.read().decode('utf-8')
print text

[xypcx]

今天又出现新错误了

python: unhashable type error

[xypcx]

恩，今天查了一下，看到了这个网站的request method是post

[xypcx]

对了， print text是不是把结果以txt文件保存？
我运行了一下你的代码，显示NameError: name 'text' is not defined
你是不是想说的是‘content’？

[China_hezt]

是的，编辑的时候打错了。