import urllib.request,http.cookiejar

url = "http://www.baidu.com"

print("第一种方法")

response1 = urllib.request.urlopen(url)

print(response1.getcode())

print(len(response1.read()))

print("第二种方法")

request = urllib.request.Request(url)

request.add_header("user-agent", 'Mozilla/5.0')

response2 = urllib.request.urlopen(request) 

print(response2.getcode())

print(len(response2.read()))

print("第三种方法")

cj = http.cookiejar.CookieJar()

opener = urllib.request.build_opener(urllib.request.HTTPCookieProcessor(cj))

urllib.request.install_opener(opener)

response3 = urllib.request.urlopen(url)

print(response3.getcode())

print(cj)

print(response3.read())