• Python：使用os.walk() 遞迴印出資料夾中所有目錄及檔名http://www.ewdna.com/2012/04/pythonoswalk.html

• Python Tutorial 第二堂（3）函式、模組、類別與套件
  http://www.codedata.com.tw/python/python-tutorial-the-2nd-class-3-function-module-class-package

class Calculator:

name = 'My Calculator'

def add(self , x , y):
    return cal('%s+%s'%(x,y))
def minus(self , x , y):
    return cal('%s-%s'%(x,y))
def times(self , x , y):
    return cal('%s*%s'%(x,y))
def divide(self , x , y):
    return cal('%s/%s'%(x,y))

def cal(calcul_string):
return eval(calcul_string)

calcul = Calculator()
print(calcul.name)
print(calcul.add(1,2))
print(calcul.minus(1,2))
print(calcul.times(1,2))
print(calcul.divide(1,2))

#excution result
'''
C:\Python34>python.exe example_class.py
My Calculator
3
-1
2
0.5
'''

eval(str)函数很强大，官方解释为：将字符串str当成有效的表达式来求值并返回计算结果。所以，结合math当成一个计算器很好用。

reference :
http://blog.csdn.net/seetheworld518/article/details/47983511
http://www.cnblogs.com/ankier/archive/2012/10/11/2719731.html

https://stackoverflow.com/questions/13293269/how-would-i-stop-a-while-loop-after-n-amount-of-time

from interruptingcow import timeout
try:
with timeout(60*5, exception=RuntimeError):
while True:
test = 0
if test == 5:
break
test = test - 1
except RuntimeError:
pass

threading.current_thread()._delete()

https://www.cnblogs.com/ListenWind/p/4624476.html

Summary :
Study Socket and write some example here

What to do :

• Sudy Socket
• Write some examples

https://stackoverflow.com/questions/6470428/catch-multiple-exceptions-in-one-line-except-block

print([x for x in itertools.permutations('1234')])

[('1', '2', '3', '4'), ('1', '2', '4', '3'), ('1', '3', '2', '4') ... ]

Summary :
Collect all the Python Basic Commands by studying

What to do :

• List the command and summary

http://translate17.com/article/1730

Summary :
Python own coding style

###############

Open a file

###############

text = 'This is my first test.\nThis is next line.\nThis is last line'

my_file = open('my_file.txt','w') #write
my_file.write(text)
my_file.close()

#################

Append a file

#################

append_text = '\nThis is appended file.'

my_file = open('my_file.txt','a') #append
my_file.write(append_text)
my_file.close()

###################

Read a txt file

###################

file = open('my_file.txt','r')
content=file.read()
print('#############################\n')
print('The resule of file.read()')
print(content)

content=file.readlines()
print('#############################\n')
print('The resule of file.readlines() without opening file')
print(content)

file = open('my_file.txt','r')
content=file.readlines()
print('#############################\n')
print('The resule of file.readlines()')
print(content)

file = open('my_file.txt','r')
content=file.readline()
content_second=file.readline()
print('#############################\n')
print('The resule of file.readline()')
print(content,content_second)

http://allenchien.logdown.com/posts/425530

def unique(old_list):
newList = []
for x in old_list:
if x not in newList :
newList.append(x)
return newList

import threading
import time

thread_join_time = 5
word = []

def run():
global stop_threads
stop_threads = False
print('thread running')
global word

time.sleep(thread_join_time+1) # This time value should large than thread_join_time
print("len(word) is :"+str(len(word)))
if len(word)>0:        
    for i in word:
        time.sleep(1)            
        print("################"+i)
        print(stop_threads)
        if stop_threads: 
            print("@@@@@@@@@@@@@@@@@@@@@@@@@@")
            print(stop_threads)
            return
    return
else:
    print("### No data , thus kill the current thread ###")
    threading.current_thread()._delete()
    print("### No data , thus kill the current thread ###")

def thread_test():
t1 = threading.Thread(target = run)
t1.start()
t1.join(thread_join_time)
global word
word = ["5","4"]

def thread_stop():
print('thread killed stop_threads=True')
global stop_threads
stop_threads=True
time.sleep(1)

def test():
print(threading.active_count())
print(threading.enumerate())
time.sleep(1)

# Linux solution to set a timeout value for a function execution
#try:
#    with timeout(5, exception=RuntimeError):
#        while True:
#            thread_test()
#except RuntimeError:
#    pass
#	



thread_test()


# Flag solution to set a flag to quit the locked thread   
#thread_stop()

print(threading.active_count()) 
print(threading.enumerate())

test()

while True:
print("1.test_1\n2.test_2\nothers for leaving")
a_input = input("Please givea number :") # return a string
if a_input == '1':
print("This test is ",a_input)
elif a_input == '2':
print("This test is ",a_input)
else:
break

def tc_Misc_00005():
case = ["test"]
SYS_SetTestCaseName(case)

Test_Day_Count = 3

print_log("Current Date is : " + SSH_Write("date")[0])
Current_Year = SSH_Write("date +%Y")[0][:-1]
Current_Month = SSH_Write("date +%m")[0][:-1]
Current_Day = SSH_Write("date +%d")[0][:-1]

if len(Current_Month) == 1:
    Current_Month = "0" + Current_Month

Test_Days = str(int(Current_Day) + Test_Day_Count)
if len(Test_Days) == 1:
    Test_Days = "0" + str(Test_Days)	

SSH_Write("date " + Current_Month + Test_Days + "1200" + Current_Year)

print_log("Current Date is : " + SSH_Write("date")[0])

https://www.geeksforgeeks.org/python-remove-last-character-in-list-of-strings/

http://www.wklken.me/posts/2013/08/20/python-extra-itertools.html

https://blog.kelu.org/tech/2017/08/01/python-selenium-xpath.html

• 瞭解Unicode
  http://ez2learn.com/basic/unicode.html

• python新手必碰到的問題---encode與decode，中文亂碼
  https://read01.com/nmyKny.html

Python PIP 安装模块报ascii码错误的问题
January 27, 2016
在Windows10与Python2.7及PIP环境下安装模块总是报编码错误，如下：

UnicodeEncodeError: 'ascii' codec can't encode character u'\u258e' in position 8: ordinal not in range(128)
这个问题的产生可能是用户的语言环境默认的编码设置所致，在网上找到解决办法，在python2.7\Lib\site-packages目录下新建一个sitecustomize.py 文件，插入代码如下：

import sys
sys.setdefaultencoding('UTF-8')
再尝试安装模块就可以通过。

http://kuma-uni.blogspot.com/2012/06/jsonpythonjson.html

jsons.load() ==> only accept {" " : " " , " " : " "}

• Python in Socket
• 用Python爬蟲

def Who_is_bigger(x,y,z):
if x>y:
print("x>y")
elif x>z:
print("xz")
else:
print("x<y and x<z")

Who_is_bigger(4,2,3)

sed -i 's/"LogEFIStatusCodes": "[A-z|0-9|:punct:|.| ]*"/"LogEFIStatusCodes": "Error code"/' /etc/bios_current.json

apple=100
a = None
def fun():
a = 20
return a+100

print(apple)
print('apast=',a)
print(fun())
print('a now=',a)

def fun2():
global a
a = 20
return a+100

print(apple)
print('apast=',a)
print(fun2())
print('a now=',a)

https://www.tutorialspoint.com/python/dictionary_get.htm

Description
The method get() returns a value for the given key. If key is not available then returns default value None.

Syntax
Following is the syntax for get() method −

dict.get(key, default=None)
Parameters
key -- This is the Key to be searched in the dictionary.

default -- This is the Value to be returned in case key does not exist.

Return Value
This method return a value for the given key. If key is not available, then returns default value None.

Example
The following example shows the usage of get() method.

#!/usr/bin/python

dict = {'Name': 'Zabra', 'Age': 7}

print "Value : %s" % dict.get('Age')
print "Value : %s" % dict.get('Education', "Never")
When we run above program, it produces following result −

Value : 7
Value : Never

https://pymotw.com/2/threading/

剛開始寫 python 的時候，看到幾乎每個程式的最後面都有一段 code:

if name == 'main':
doSomething()

一直都不懂那是什麼意思，只知道要照抄然後執行程式時那段就會被執行。後來深入研究之後才比較瞭解 name 的意思了。

原來如果一個 python script 是被別的 python script 當成 module 來 import 的話，那麼這個被 import 的 python script 的 name 就會是那個 python script 的名稱。而如果這個 python script 是直接被執行的話，name 就會是 main。

舉例來說，如果我有一個程式叫做 myModule.py，內容就是一行顯示自己的 name:

print 'name:' + name

那麼我直接執行它的話，結果會顯示 main:

bash-3.2$ python myModule.py
name:main

但如果我準備了另一個程式叫做 testModule.py，裡面就這麼一行去 import myModule:

import myModule

然後我去執行 testModule.py 的話，則會顯示 myModule:

bash-3.2$ python testModule.py
name:myModule

所以用 name 就可以分辨我的程式是被 import 當成模組還是被直接執行的。這樣附帶的好處就是如果我寫的程式平常可以被 import 來使用，但有時它自己也可以直接執行。其它語言的話，可能就要區分 library 跟使用 library 的程式，而 python 的話這兩者的界線就很模糊。