String immutability in Python - Mini Project: Build & Apply

Understanding String Immutability in Python

📖 Scenario: Imagine you are managing a list of usernames for a website. You want to update a username by changing one letter, but you need to understand how strings work in Python to do this correctly.

🎯 Goal: You will learn how strings cannot be changed directly (immutable) and how to create a new string with the desired changes.

📋 What You'll Learn

Create a string variable with a username

Create a variable for the position of the character to change

Create a new string with the changed character using string slicing

Print the new username

💡 Why This Matters

🌍 Real World

Usernames, passwords, and other text data often need to be updated carefully without changing the whole string.

💼 Career

Understanding string immutability is important for software developers to manipulate text data correctly and avoid errors.

1

Create the initial username string

Create a string variable called username and set it to the value "pythonista".

Python

# Create a string variable called username with the value "pythonista"
# Your code here

Need a hint?

Use quotes to create a string. For example: name = "hello"

2

Set the position of the character to change

Create an integer variable called position and set it to 6 to represent the index of the character to change in username.

Python

username = "pythonista"
# Create an integer variable called position and set it to 6
# Your code here

Need a hint?

Remember that string indexes start at 0. The 7th character has index 6.

3

Create a new username with the changed character

Create a new string variable called new_username by combining the part of username before position, the letter 's', and the part of username after position. Use string slicing and concatenation.

Python

username = "pythonista"
position = 6
# Create new_username by replacing the character at position with 's'
# Your code here

Need a hint?

Use username[:position] to get the part before, and username[position+1:] to get the part after the character.

4

Print the new username

Write a print statement to display the value of new_username.

Python

username = "pythonista"
position = 6
new_username = username[:position] + 's' + username[position+1:]
# Print the new_username
# Your code here

Need a hint?

Use print(new_username) to show the result.