Python Variable Functions Tutorial – Complete Guide

In this article, we’ll venture into the world of Python, focusing on an essential topic – variable functions. Have you ever wondered how you can create dynamic and reusable chunks of code that can perform various tasks based on input values? If so, you are about to embark on a fascinating and enlightening journey to demystify Python variable functions.

What are Python Variable Functions?

Variable functions in Python, also known as ‘functions’, are reusable chunks of code designed to perform a specific task. These functions can take inputs, known as arguments or parameters, which determine how the function behaves.

Variable functions bring immense value to your coding repertoire. They are crucial in avoiding repetition, enhancing code readability, and partitioning complex tasks into manageable steps. They’re the building blocks of clean and efficient code.

Learning variable functions in Python can take your coding to the next level. It enables you to write succinct, readable, and highly maintainable code, a skill that’s highly sought-after in the realms of data science, web development, game development, and more. They can turn a complex task, such as score calculation in a game, into a simple, one-line action. Above all, they are fundamental to Python – and almost every other programming language.

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Defining a Function in Python

To declare a function in Python, you use the keyword ‘def’, followed by the function name and parentheses. Inside the parentheses, you can specify any necessary parameters. A colon indicates the beginning of the function body.

Let’s start with a simple function that prints out a message:

def greet():
  print("Hello, World!")

greet()  # This will output: Hello, World!

A function doesn’t do anything until it’s called. In the above example, we call the function ‘greet()’, and it’ll print “Hello, World!”.

Python Functions with Parameters

Python functions become more powerful with parameters. Parameters allow you to pass values into your functions. In the function definition, we specify parameters inside the parentheses.

def greet(name):
  print(f"Hello, {name}!")

greet("Alice")  # This will output: Hello, Alice!

In the example above, ‘name’ is a parameter. You may add more than one parameter by separating them with a comma.

Python Functions with Default Parameter Values

Python also allows you to set default values for parameters.

def greet(name="World"):
  print(f"Hello, {name}!")

greet()  # This will output: Hello, World!
greet("Alice")  # This will output: Hello, Alice!

In this example, if a name is not provided, the function uses the default value “World”.

Python Functions with Return Values

Python functions are not limited to printing messages. They can return values – and this is where they really shine!

def add_numbers(num1, num2):
  return num1 + num2

total = add_numbers(3, 5)
print(total)  # This will output: 8

In the above example, the ‘add_numbers()’ function returns the sum of two numbers, which you can store in a variable or use directly.

Since Python allows functions to be flexible and powerful, we hope that you’ve been able to see why variable functions are an essential part of Python, and indeed, any programming venture.

Python Function: Multiple Return Values

Python functions can return multiple values in the form of a tuple, which you can then unpack into individual variables.

def get_scores():
  math_score = 85
  science_score = 90
  english_score = 95
  return math_score, science_score, english_score

math, science, english = get_scores()
print(math)  # This will output: 85
print(science)  # This will output: 90
print(english)  # This will output: 95

Python Variable-Length Arguments

Python allows you to declare functions that can take an arbitrary number of arguments.

def add_numbers(*args):
  return sum(args)

result = add_numbers(3, 5, 8, 1) 
print(result)  # This will output: 17

In the above example, *args permits the function to accept any number of positional arguments, which are then processed as a tuple.

Python Keyword Arguments (kwargs)

Python also supports keyword arguments, which means you can pass arguments with a keyword.

def identify_animal(**kwargs):
  for key, value in kwargs.items():
    print(f"{key}: {value}")

identify_animal(Name="Lion", Color="Yellow", Type="Carnivore")

In this sample, **kwargs allows the function to accept any number of keyword arguments, which it processes as a dictionary.

Python Lambdas – Anonymous Functions

Python provides a way to create small anonymous functions, known as lambdas.

double = lambda x: x * 2

print(double(5))  # This will output: 10

In this case, the lambda function takes one argument and doubles it.

From the most basic operation to complex data manipulations, Python functions are your go-to resource for clean and efficient coding. Get in the habit of encapsulating operations into functions for more efficient, reusable, and scalable code.

Where to Go Next

Learning Python variable functions is only one step in the journey to becoming a proficient coder. It’s essential to continue practicing and expanding your understanding of Python and programming as a whole. In truth, there is no limit to what you can achieve with the knowledge and creativity you’ve started to nurture.

As your next step, we recommend exploring our Python Mini-Degree. This comprehensive collection of Python programming courses will expand your python knowledge beyond variables functions. It covers everything from the basics to complex topics such as algorithms, object-oriented programming, and using famous libraries such as Pygame, Tkinter, and Kivy for game and app development.

Whether you’re a complete beginner in Python or relatively experienced, our Python Mini-Degree is designed to accommodate your needs. It offers project-based assignments and flexible learning options, enabling you to improve your skills at your own pace. The courses undergo regular updates, ensuring you also keep in step with the latest industry practices.

For even more options, we invite you to check out our wide array of Python courses. We aim to cater for everyone’s needs, from people just starting their coding journeys to those who have already learned the basics and wish to further their knowledge. With Zenva, you have the chance to go from beginner to professional.

Keep learning, keep practicing, and soon enough, you’ll be writing clean, efficient, and powerful Python code with ease. Embrace the journey!


In the world of coding, learning about Python variable functions is akin to unlocking a new superpower. It opens the door to cleaner, more manageable, and robust code. This invaluable skill can be a stepping stone to vast programming domains, from web development and game creation to automating tasks and data analysis.

Your journey begins here, but it certainly doesn’t end. We encourage you to delve deeper into Python and its unique capabilities. There’s no limit to what you can achieve with the right knowledge and a dash of creativity. To keep fuelling your journey, we invite you to explore our comprehensive Python Mini-Degree, where you can get your hands dirty with all things Python. At Zenva, we believe in empowering individuals to turn their dreams into reality. Happy coding!

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