Python Modules and Packages

1. Module

1. In Python, a. py file is called a module.

2. Large Greatly improves the maintainability of the code.

3. Writing code does not have to start from scratch. When a module is written, it can be referenced elsewhere

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2. Package

* What if different people write the same module name? To avoid conflicting module names, Python introduces a way to organize modules by directory, called packages

* Steps to create a package:

(1) Create a directory for the package name;

(2) Under this folder, create a __init__.py file to store the package information, the file can be empty ;

(3) To store script files, compiled extensions and sub-packages as required;

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* Use of the package

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3. Three ways to call the module

(1) Import Manu direct call module

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(2) method in the From Manu Import add call module

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(3) From Manu Import add as Myadd call the method in the module and rename

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4. Module Search Path

1. When we try to load a module, Python searches for the corresponding. py file under the specified path;

2. By default, the Python interpreter searches the current directory, all installed built-in modules, and third-party modules, and the search path is stored in the PATH variable of the SYS module .

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3. Add the search path, which is temporary in bash.

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Python Modules and Packages