python notes 、 Script parameters 、 Bytecode

-- The heart

python install

1、 Download installation package

https://www.python.org/downloads/

2、 install

Default installation path :C:\python27

3、 Configure environment variables

【 Right click the computer 】--》【 attribute 】--》【 Advanced system setup 】--》【 senior 】--》【 environment variable 】--》【 Find... In the second content box A variable called Path A line , double-click 】 --> 【Python The installation directory is appended to the variable value , use ; Division 】

Such as : The value of the original ;C:\python27, Remember that there is a semicolon in front of you

notes

Single-line comments      #

eg:

 # print “123”

Multiline comment    “””            “””

( Start with three quotes 、 end )

eg:

“””


import sys


print sys.argv


print ' Hello , The world '


“””

style="background-color: #ff0000;"> Script parameters

Python There are a lot of modules , So that development Python The program is very simple . Class library includes three middle schools :

  • Python Internal modules
  • Open source modules in the industry
  • Modules developed by programmers themselves

eg:

newly build hello.py

#!/usr/bin/env python


# -*- coding:utf-8 -*-


import sys


print sys.argv


print ' Hello , The world '


# Capture parameters

Input : python  hello.py  localhost:8001

Output : ['hello.py', 'localhost:8001']

Hello , The world

Bytecode

eg:

newly build hello.py file

#!/usr/bin/env python


# -*- coding:utf-8 -*-


print ' Hello , The world '


# Bytecode


import m


print "hello"

newly build m.py file

#!/usr/bin/env python


# -*- coding:utf-8 -*-


print "hello daoxin"

Input :python  hello.py  localhost:8001

Output : Hello , The world

hello daoxin

hello

Execution process : hello.py Will import m.py The mold in

Be careful : If m.pyc And m.py Perform the same function , Direct execution m.pyc ; If the function is different , perform m.py Post formation m.pyc Re execution

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