Basics of Chapter V module

5.1 Basics module

1. Modules (library) Category

• • Built-in modules, the functionality provided inside python

    Import SYS # Import Module is loaded into memory priority Print ( SYS, the argv)  
    

  • Third-party modules, download, install, use

    1. PIP package management tool . The PIP EXE file is located in the directory to environment variable PIP install to install the module name # pip install xxxx 2. Source Installation Download Source Package: compressed files. Unzip the file open cmd window, and enter the directory: cd C: \ Python36 \ Lib \ Site - Packages Standard Package execution: python36 Setup. Py Build execution: python36 Setup. Py install
        
        
    
    
        
        
        
        
        

  • Custom Modules

  1. 1. New xxx.py file

        def f1():
            print('f1')
        def f2():
            print('f2')

     2. New x1.py file

        # Module calls the custom function 
        # a manner  directly into the module, all functions 
        Import XXX 
        XXX. F1 () 
        XXX. F2 () # Second way to import the specified function from XXX Import F1, F2 ( from XXX Import *) # prevent variable names repeated from xxx Import f1 AS f f1 ()
        
        
        
        
        
        
        

     3. run

        python x1.py

2. Modules may be a py file as a module for later py file calls other functions of certain aspects of file

3. Calling module package, including: folders, files stored in multiple folders py

   If a package is imported, the default bag module can not be used

   Introducing a package corresponds to the implementation of __init__the content file py

   • abc.py file contents

     # abc.py
     def func():
         print(1,2,3)
     ​
     def show():
         print(4,5,6)
     ​
     print("你好")

   • Import module, the module loading all values ​​into memory

     Import ABC Print ( . 7, . 8, . 9) function call to the module # ABC. FUNC () # l, 2,3, hello 7,8,9
     
     
     
     

4. The method of introducing the module

   • import

     • import function module 1. Module 1 ()

     • import module 1. Module 1 Module 2 Module 3 Module 2 Module 3 function ()

   • from xx import xxx

     • from module import function module function ()

     • from module import function module as ff ()

     • from module 1 function module import * () function 2 ()

     • from module import module module function ()

     • import module from the module as m m. function ()

   • Multiple imports only imported once

     # Example of an 
     Import jd # first load: loaded again in all of the content jd. 
     Import JD # has been loaded by, not loaded. 
     Print ( 456) # two exemplary Import the importlib Import JD the importlib. reload ( JD) Print ( 456)
     
     
     
     
     
     

      

   • Special case

     

   1         # manner as a function of all imported modules 
   2               import ABC
    . 3               abc.func ()
    . 4  . 5 # second approach . 6 from ABC import FUNC     # # from import function module . 7 from ABC import Show
    . 8 from ABC import FUNC, Show    # from module import function / function () . 9 from ABC import *
    10 . 11 from ABC import FUNC F AS    #        
                 
                               
                                 import function module from an alias as an alias () 

    

5. to sum up

   • And py module file to be executed in the same directory and requires a lot of features in the module, recommended: import module

   • Other Recommendations:. From module import module / module function ()

   • Other Recommendations:. From module import function module function ()