Introduction to module and package concepts in Python

The module overview

If modules are the way to organize Python code logically, then files are the way to organize modules at the physical level.
Therefore, **1 file is regarded as a separate module, and 1 module can also be regarded as a file. The file name of a module is the module
The name of the block with the extension.py. Unlike other languages that can import classes (class), in Python you import modules or module properties **.

Module namespace

A namespace is a relational mapping of a name to an object.

The import module

Import module whole (import)

Method 1

import module1

import module2

...

import moduleN

Way 2

import module1[, module2[,... moduleN]]

Import module properties (from... import...).

Calling from-import imports the name into the current namespace, which means you don't need to use the property/period property identifier to access the module's identifier. For example, you need to access the var name in the module module to be imported like this:

from module import name1[, name2[, ...  nameN]]

Rename the module or property after import

import ... as ...

from ... import ... as ...

package

A package is a hierarchical file directory structure, with modules corresponding to a single file and packages corresponding to a directory. Causes the module in the package to be imported with standard import and from-import statements.