[CWC]

Python functions and classes are two most important things when it comes to programming. So, I have decided to make this article to tell you about the functions in Python. So, let’s start!

What is a function?

Functions in Python are used to perform different tasks. A function is a set of instructions that is executed by the computer.

Functions in Python are written using the keyword def. You can also define functions using def function_name(arg1, arg2, arg3).

Here arg1 is the first argument of the function and arg2 is the second argument. The third argument is optional.

A function is considered to be a class in Python. Let’s take an example:

>>> def add(a, b):

… return a + b

So, we have defined a function add, and it is defined as def add(a,b). Now, let’s see how it works:

>>> add(2, 3)

5

So, we have used the function add, and passed the arguments 2 and 3.

Functions are used to perform different tasks like calculating the sum of two numbers.

So, now, let’s see some examples of functions.

Defining a function with parameters

Let’s say we want to create a function called square_root and we want to use it to calculate the square root of a number. The syntax of the function is:

def square_root(number):

The parameters of this function are:

number: This is the argument of the function.

So, if you want to pass the number as the parameter, you can do it like this:

>>> print(square_root(4))

2

>>> print(square_root(5))

So, you can easily see the output.

Let’s see some more examples.

Defining a function without any arguments

Another way of defining a function is to define the function without any arguments.

Let’s say, if you want to make a function that will return the square root of a number, you can do it like this:

>>> def square_root():

… return 2

You can see that the function is without any arguments.

Let’s check the output.

>>> print(square_root())

2

>>> print(square_root(10))

>>>

So, we have created a function that returns the square root of a number.

Let’s make a function that will return the factorial of a number. The syntax of the function is:

def factorial(n):

The parameters of this function are:

n: This is the argument of the function.

So, if you want to pass the number as the parameter, you can do it like this:

>>> print(factorial(5))

120

You can see the output.