Python Modules Introduction Tutorial – Complete Guide

In the dynamic world of programming, Python has emerged as one of the go-to languages for beginners and experts alike. Its readability and flexibility have made it not only user-friendly but also robust for a plethora of applications. One such feature that adds to this robustness is Python’s Modules.

What are Python Modules?

Python modules are an integral part of the Python landscape. They are essentially python scripts (*.py files) that consist of Python code. They are designed in a way that enables you to logically organize your Python code, making it more understandable and easier to manage.

Why Should You Learn About Python Modules?

Python modules are, in essence, toolkits for various programming tasks. By mastering Python Modules, you’ll unlock:

  • An efficient way to reuse code.
  • A method for logically organizing code into manageable chunks which in turn can make your code more understandable and maintainable.
  • Access to a vast array of built-in and third-party modules, each with useful capabilities to expand your Python prowess.

Think of Python modules like a new level in a video game. Once you’ve mastered it, you’ll have new abilities that make completing further challenges easier and more enjoyable!

Next, we’ll be diving into the practical application of Python Modules. Isn’t it exciting to learn by doing? Let’s move on.

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Using Python Modules

Let’s start this journey by learning how to import Python modules.

import math

Here we have imported the built-in math module. You can now access various mathematical functions like sqrt or log using the dot operator.


Importing Specific Attributes

To import specific attributes or functions from a module, you can use the from keyword.

from math import sqrt

Now, you can directly use the sqrt function without the math. prefix.

Alias a Module

In Python, you can create an alias for your module at the time of importing. This is done with the as keyword.

import math as m

Here we are creating an alias “m” for the “math” module. The alias reduces typing when our module name is lengthy.

Built-in Module Functions: dir() and help()

Python additionally provides built-in functions to interact with the modules, i.e., dir() and help() functions.

print(dir(math)) #returns a list of all the functions in math module

help(math.sqrt) #to know what the sqrt function does

The dir() function helps in finding out what identifiers are defined in a module. The help() function is used to get a brief description of how to use the particular function or method in Python.

In the next section, we will cover creating and running your custom Python modules. Make sure you are ready for the next level!

Creating a Python Module

Creating your own Python module is as simple as creating a python file. Let’s consider a python file which has a function add().

def add(a, b):
  return a+b

You have just created your own Python module named demo.

Importing and Using Your Own Python Module

You can import your custom module just like you import built-in modules.

import demo


You can also import a specific function from your module.

from demo import add


Reloading a Module

Python’s import statement only imports a module the first time it encounters the import command. If you want to load changes you’ve made to your module without closing the python interpreter, you use the reload() function from the importlib module.

import importlib

Python’s if __name__ == “__main__” Construct

Often, when you’re writing a module, you might want to execute some of the code in the module for testing purposes, but you don’t want that code executed when you import the module. This is where Python’s if __name__ == “__main__” construct comes in handy.

def print_hello():
  print("Hello from a module")

if __name__ == "__main__":

Here, if you run the file directly, Python will execute the code in the if condition. But if you import from another file, Python will not execute the code in the if condition.

Python’s Package and Sub-package

When your application grows larger, it’s a good practice to organize your modules into directories. A directory must contain a file named for Python to consider it as a package or sub-package.

# mypackage/

Here, mypackage is a Python package. Now you can put your modules inside mypackage and import them using the package name.

import mypackage.demo

Don’t be alarmed if it looks like we’ve thrown lots of new concepts at you. Take your time, practice, and soon, you’ll be comfortably using Python Modules like a pro. Remember, Rome wasn’t built in a day, and neither is a programmer!

Where to Go Next?

You’ve just taken your first steps into the intriguing world of Python modules, but that’s just the beginning. As you might have noticed, programming, and Python in particular, is an expansive and multifaceted subject. There’s plenty more to learn, discover, and create!

We encourage you to deepen and expand your Python knowledge with our Python Mini-Degree. This program doesn’t solely rely on passing on theoretical knowledge. Instead, it focuses on active learning through creating real-life apps, games, and algorithms. By working your way through practical, step-by-step projects, you not only acquire invaluable skills, but you also build up a professional portfolio.

Our instructors, accredited by renowned organizations such as Unity Technologies and CompTIA, guide you through versatile Python topics. These range from coding basics and data handling to more advanced aspects like algorithms and game development. You can access these informative and engaging courses 24/7 and work at your pace.

Looking for something specific within the Python sphere? Don’t forget to check our Python courses page. It’s a broad collection of Python-specific content, suitable for professionals at all stages of their learning journey.

Becoming a proficient programmer isn’t achieved overnight—it requires perseverance, practice, and continuous learning. But with dedication, the right mindset, and Zenva on your side, you’re well on your way from beginner to professional. Let’s conquer Python together!


From logical code organization to reusable code, Python modules hold the promise to supercharge your Python capabilities. They are stepping stones in your journey to becoming a versatile Python programmer, a journey filled with exciting discoveries and creations. As you continue to dive deeper, never underestimate the value of practice and the power of passion.

At Zenva, we look forward to accompanying you on this remarkable journey. With our comprehensive Python Mini-Degree, we empower you with everything you need, from the basics to the advanced, from foundational concepts to real-world projects. Today, you might be a beginner; tomorrow, you’ll be a professional. Sew the seeds of this transformation with Python Modules, and let’s change the world, one line of Python at a time!

Did you come across any errors in this tutorial? Please let us know by completing this form and we’ll look into it!

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