「PYTHON」- 模块类库 | Module | 组织代码的单元

认识

将代码分成多个文件或模块，提高代码的可维护性和重用性。

组成

Module —— the basic unit of code reusability in Python: a block of code imported by some other code. Three types of modules concern us here:

pure Python modules

a module written in Python and contained in a single .py file (and possibly associated .pyc files). Sometimes referred to as a “pure module.”

简而言之，其仅包含 Python 代码。

extension modules

a module written in the low-level language of the Python implementation: C/C++ for Python, Java for Jython. Typically contained in a single dynamically loadable pre-compiled file, e.g. a shared object (.so) file for Python extensions on Unix, a DLL (given the .pyd extension) for Python extensions on Windows, or a Java class file for Jython extensions. (Note that currently, the Distutils only handles C/C++ extensions for Python.)

简而言之，该类模块包含平台相关代码。

性质

__all__ = []

It is a list of strings defining what symbols in a module will be exported when from <module> import * is used on the module.
__all__ affects the from <module> import * behavior only. Members that are not mentioned in __all__ are still accessible from outside the module and can be imported with from <module> import <member>.

What does all mean in Python?

import <module_name>

‘import’ vs ‘from import’ in Python — What’s The Difference?

import os
import os as RealOs

import datetime
d1 = datetime.date(2021, 10, 19)

import *

the default behaviour of import * is to import all symbols that do not begin with an underscore, from the given namespace.

from <module_name> import <class/func>

PEP 221 — Import As | Python.org
python – How do I call a function from another .py file? – Stack Overflow
How to Import Class from Another File in Python | by Teamcode | Medium

from os import path as p

# --------------------------------------------------------- # Import a Class

from myclass import MyClass
my_instance = MyClass()

# --------------------------------------------------------- # Import a Function

from filebar import funcbar
funcbar(a, b)

构建

安装模块：Installing Python Modules
发布模块：Distributing Python Modules

应用

如何通过“绝对路径”来使用模块名

针对部分模块，我们很少使用，所以我们并不想使用 import 语句来导入模块，而是希望直接使用模块。

# python
Python 3.12.10 (main, May  1 2025, 20:33:51) [GCC 14.2.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> a=1
>>> b=2
>>> print(__import__('operator').lt(a,b))
True
>>>