[Python] Frequently used method or solutions for issues

• Web Scraping爬虫  for Mac urllib.error.URLError: <urlopen error [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:581)>

Solution:  if 1) does not work, then try to use 2).  Reference is here.

　　　　　　　　1)

　　pip install --upgrade certifi

　　　　　　　　2)

open /Applications/Python\ 3.6/Install\ Certificates.command

• if running a python file to use https call, have error like
  "SSLError(1, u'[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:661"

　　　　Solution:

　　　　　　then solve it by adding

configuration.verify_ssl = False

in the test file.
Then it will skip verifying SSL certificate when calling API from https server.

• if running a python file to use https call, have the warning of InsecureRequestWarning

　　　　Solution:

　　　　　　then solve it by adding

import urllib3
urllib3.disable_warnings()

in the test file. 
Then it will skip warning.

• Remove leading whitespace 去除string前面的空格

　　　　Solution:

>>> '     hello world!'.lstrip()
'hello world!'

• Web Scraping爬虫

  看网页编码方式( 一般为“utf-8”)

　　　　Solution: F12功能键，即可使用开发者工具，在窗口console标签下，键入 "document.charset" 即可查看网页的编码方式