初学python 遇到的坑

这最近人工智能比较火，看了一下大多都是python的代码，最近看看python 的代码，一出来就遇到了坑,空格的问题先不说了直接上代码吧

# coding = utf-8
import urllib.request
#import ssl

#ssl._create_default_https_context = ssl._create_unverified_context
response = urllib.request.urlopen('https://www.douban.com/')
print(response.read().decode('utf-8'))

　　

python python3 log_python.py
Traceback (most recent call last):
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1318, in do_open
encode_chunked=req.has_header('Transfer-encoding'))
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1239, in request
self._send_request(method, url, body, headers, encode_chunked)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1285, in _send_request
self.endheaders(body, encode_chunked=encode_chunked)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1234, in endheaders
self._send_output(message_body, encode_chunked=encode_chunked)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1026, in _send_output
self.send(msg)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 964, in send
self.connect()
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/http/client.py", line 1400, in connect
server_hostname=server_hostname)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/ssl.py", line 401, in wrap_socket
_context=self, _session=session)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/ssl.py", line 808, in __init__
self.do_handshake()
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/ssl.py", line 1061, in do_handshake
self._sslobj.do_handshake()
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/ssl.py", line 683, in do_handshake
self._sslobj.do_handshake()
ssl.SSLError: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:749)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "log_python.py", line 6, in <module>
response = urllib.request.urlopen('https://www.douban.com/')
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 223, in urlopen
return opener.open(url, data, timeout)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 526, in open
response = self._open(req, data)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 544, in _open
'_open', req)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 504, in _call_chain
result = func(*args)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1361, in https_open
context=self._context, check_hostname=self._check_hostname)
File "/usr/local/homebrew/Cellar/python3/3.6.0/Frameworks/Python.framework/Versions/3.6/lib/python3.6/urllib/request.py", line 1320, in do_open
raise URLError(err)
urllib.error.URLError: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:749)>

出了一堆的错，然后在 http://stackoverflow.com/questions/27835619/ssl-certificate-verify-failed-error 找到了答案:

要引入 一个ssl 的模块，然后，就没有然后了

Could not fetch URL https://pypi.python.org/simple/nltk/: There was a problem confirming the ssl certificate: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:749) - skipping
  Could not find a version that satisfies the requirement nltk (from versions: )
No matching distribution found for nltk

报了上面的错，下面的语句解决.

pip --trusted-host pypi.python.org install

<urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:645

　报了上面的错，下面的语句解决　

pip3 install certifi