Python basic 5 common modules

1. Definition:

A module used to logically organize Python code (variables, functions, classes, logic: Implementing a function), essentially the. PY result of the Python file (file name: test.py corresponding module name: TEST) Package: It is used to logically organize the module, which is essentially a directory ( Must have a __init__.py file)

2. How to Import

Import module_name #导入一个模块import module_name,module2_name #导入多个模块from module_name Import * #定义导入模块下所有的方法导入 Operation not recommended) from MODULE_NAME import M1 m2 m3from module_name import logger as Logger_alex

3.import Nature (Path search and search path)

The essence of the import module is to interpret the Python file once (import Test test= ' test.py All code ' defines a variable test, which points to the area of memory) (from test import name name= ' code ') IM Port module_name----->module_name.py Path--->sys.path-----the >module_name.py

The essence of the import package is to execute the __init__.py file under the package

4. Import optimization

From module_name import test as Test_one #执行导入模块test, import once, use the test method multiple times

5. Classification of modules:

A: standard library B: Open source module C: Custom module

Python basic 5 common modules