Python Modules and Packages: Structuring Your Code

Python modules are files containing Python code. They can be imported into other Python modules or scripts to provide additional functionality. Modules can define functions, classes, and variables, and can also include runnable code.

To create a module, you can save a file with a .py extension. For example, you can create a module called "my_module.py" containing the following code:

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def greet(name):

  print("Hello, " + name + "!")

To use this module in another script, you can use the import statement. For example:

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import my_module

my_module.greet("John") # Output: "Hello, John!"

You can also import specific objects from a module using the from ... import ... statement. For example:

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from my_module import greet

greet("Jane") # Output: "Hello, Jane!"

You can also give a module a different alias using the as keyword. For example:

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import my_module as mm

mm.greet("Mike") # Output: "Hello, Mike!"

Python packages are a way to structure your code into logical modules. A package is a directory containing multiple modules, and can also contain sub-packages.

To create a package, you can create a directory and place your modules in it. You can also create an init.py file in the directory to initialize the package. The init.py file can be an empty file, or it can contain code that runs when the package is imported.

For example, you can create a package called "my_package" containing two modules: "module1.py" and "module2.py". The directory structure would look like this:

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my_package/

  __init__.py

  module1.py

  module2.py

To use the modules in the package, you can use the import statement with the package name and the module name. For example:

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import my_package.module1

import my_package.module2

my_package.module1.func1()

my_package.module2.func2()

You can also use the from ... import ... statement to import specific objects from a package or module. For example:

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from my_package import module1

from my_package.module2 import func2

module1.func1()

func2()

Using modules and packages can help you organize and structure your code, and make it easier to reuse and maintain. It is a good practice to follow when developing larger projects.