Creating a Module in Python

Python is a high-level programming language that’s not only easy to learn but also offers various features for creating complex applications. It has a vast standard library that offers various modules that can be imported to use in your application. However, sometimes standard modules may not meet all your requirements, or you may want to create a module that caters to your specific needs. In this article, we will cover how to create a module in Python and how to import it into an application.

Creating a Module:

A module is a file containing Python code. It can contain functions, classes, and variables that can be imported and used in other programs. To create a module, follow the steps below:

1. Create a Python file:

Open a text editor or an IDE and create a new file. Save it as module_name.py. The filename should be in snake_case, and the extension must be .py. This will indicate that it’s a Python module.

2. Define module functions:

Inside the module, define the functions you want to include. For example:

def add_numbers(x, y):
    '''
    This function adds two numbers.
    '''
    return x + y

def multiply_numbers(x, y):
    '''
    This function multiplies two numbers.
    '''
    return x * y

Here we have defined two functions, add_numbers, and multiply_numbers. These functions will now be available in our module.

3. Import module functions:

Now that we have defined the module, we can import it into our program to use its functions. To import a module, use the import statement. For example:

import module_name

result = module_name.add_numbers(2, 3)
print(result)

Here, we have imported the module_name module and used its add_numbers function.

Creating a Package:

If you have multiple modules that belong to the same category, it’s better to organize them into a package. A package is a collection of modules inside a directory. To create a package, follow the steps below:

1. Create a directory:

Create a directory that will contain all the modules. The directory name should be in snake_case.

2. Create a __init__.py file:

Create an __init__.py file inside the directory. This file can be left blank, or it can contain initialization code for the package.

3. Create module files:

Create Python files inside the directory containing the modules you want to include in the package. Here is an example of how to organize the files:

package_name/
    __init__.py
    module1.py
    module2.py

4. Import package modules:

To import modules from a package, use the dot notation. For example:

import package_name.module1

result = package_name.module1.add_numbers(2, 3)
print(result)

Here, we have imported the add_numbers function from the module1.py file of the package_name package.

Conclusion:

Creating your modules and packages in Python is easy and enables you to organize your code and improves your application’s performance. By creating reusable modules, you can save time and focus on solving more complex problems.