diff --git a/docs/source/notes/python-rexp.rst b/docs/source/notes/python-rexp.rst
index c0ad72b1..64241d23 100644
--- a/docs/source/notes/python-rexp.rst
+++ b/docs/source/notes/python-rexp.rst
@@ -2,6 +2,67 @@
Python Regular Expression cheatsheet
====================================
+Compare HTML tags
+-----------------
+
++------------+--------------+--------------+
+| tag type | format | example |
++============+==============+==============+
+| all tag | <[^>]+> |
, |
++------------+--------------+--------------+
+| open tag | <[^/>][^>]*> | , |
++------------+--------------+--------------+
+| close tag | ]+> | , |
++------------+--------------+--------------+
+| self close | <[^/>]+/> |
|
++------------+--------------+--------------+
+
+
+.. code-block:: python
+
+ # open tag
+ >>> re.search('<[^/>][^>]*>', '') != None
+ False
+
+ # close tag
+ >>> re.search(']+>', '
') != None
+ True
+
+ # self close
+ >>> re.search('<[^/>]+/>', '
') != None
+ True
+
+``re.findall()`` match string
+-----------------------------
+
+.. code-block:: python
+
+ # split all string
+ >>> re.findall('[\w]+', source)
+ ['Hello', 'World', 'Ker', 'HAHA']
+
+ # parsing python.org website
+ >>> import urllib
+ >>> import re
+ >>> s = urllib.urlopen('https://www.python.org')
+ >>> html = s.read()
+ >>> s.close()
+ >>> print "open tags"
+ open tags
+ >>> re.findall('<[^/>][^>]*>', html)[0:2]
+ ['', '