What is Function?

The function is a block of code that performs a specific task. In Python programming define a function we use the def keyword. The function provides reusable pieces of code. The function is mainly two types:

• Built-in functions
• User-defined functions

Built-in functions:

These functions are defined and pre-coded in Python. Some examples of built-in functions are as follows:

• min()
• max()
• len()
• sum()
• type()
• range()
• dict()
• list()
• tuple()
• set()
• print()

User-defined functions:

That function is defined by the developer according to the user’s requirement, that is user-defined functions. In Python using def keywords we can create functions. Let’s see how we can create functions:

Syntax:

def function_name(parameters):
    # Function body
    # Code to perform a specific task

Example:

def greet():
    # This function greets the user with the provided name.
    print("Hello Priti!")
    

# Function call
greet()

we will call by function name to execute the block of code.

The Output Of This Code Will Be:

Hello Priti!

Function With Parameters:

We can specify the parameters in the function definition. Parameters are the values that the function receives when you call it. Let’s see the example:

def greet(name):
    # This function greets the user with the provided name.
    print("Hello", name)


# Function call
greet("Priti)

The Output Of This Code Will Be:

Hello Priti!

Let’s see another example for a better understanding.

def add_numbers(x, y):
    sum_result = x + y
    print (sum_result)

# Function call
add_numbers(5, 3)

In this example, the add_numbers function has two parameters, x and y. When calling the function [add_numbers(5, 3)] we can pass the value. This is called arguments and x, and y are parameters.

The Output Of This Code Will Be:

8

Return Statement:

The function can return a result. The return keyword is used to return some value from the function. User-defined functions help in making your code modular, and they assist you in managing a task by dividing it into different functions. Let’s see an example:

def add_numbers(x, y):
    sum_result = x + y
    return sum_result

# Function call
result = add_numbers(5, 3)
print("Sum:", result)

The Output Of This Code Will Be:

Sum: 8

Default Arguments:

We can set default values in the function. If we do not provide any values at function calling time this default value will be used.

def greet_with_name(name="Guest"):
    print("Hello, " + name + "!")

# Call the function:
greet_with_name()
greet_with_name("Shivam")

The Output Of This Code Will Be:

Hello, Guest!
Hello, Shivam!

I hope you understand Functions in Python. If you do not understand this topic just comment below with your email ID, and I will mail back to you.