String length and membership test in Python - Mini Project: Build & Apply

String length and membership test

📖 Scenario: You are working on a simple program that checks details about a username entered by a user. This is common when signing up for websites or apps.

🎯 Goal: You will create a program that stores a username, checks if it contains a special character, and then prints the length of the username and whether the special character is present.

📋 What You'll Learn

Create a variable called username with the exact value 'user_123'.

Create a variable called special_char with the exact value '_'.

Use the in keyword to check if special_char is in username and store the result in a variable called has_special.

Use the len() function to find the length of username and store it in a variable called length.

Print the values of length and has_special exactly as shown.

💡 Why This Matters

🌍 Real World

Checking usernames or passwords for special characters and length is common in sign-up forms to ensure security and proper formatting.

💼 Career

Understanding string operations like length and membership tests is essential for roles in software development, quality assurance, and data processing.

1

Create the username variable

Create a variable called username and set it to the string 'user_123'.

Python

# Create the username variable
# Your code here

Need a hint?

Use the equals sign = to assign the string 'user_123' to username.

2

Create the special character variable

Create a variable called special_char and set it to the string '_'.

Python

username = 'user_123'
# Create the special_char variable
# Your code here

Need a hint?

Assign the underscore character '_' to the variable special_char.

3

Check for special character and find length

Create a variable called has_special that is True if special_char is in username, otherwise False. Also create a variable called length that stores the length of username using the len() function.

Python

username = 'user_123'
special_char = '_'
# Check if special_char is in username and store in has_special
# Find length of username and store in length
# Your code here

Need a hint?

Use the in keyword to check membership and len() to get string length.

4

Print the results

Print the value of length and then print the value of has_special on separate lines.

Python

username = 'user_123'
special_char = '_'
has_special = special_char in username
length = len(username)
# Print length and has_special
# Your code here

Need a hint?

Use two print() statements, one for length and one for has_special.