Why strings are used in Python - See It in Action

Why Strings Are Used

📖 Scenario: Imagine you are creating a simple contact list app. You need to store names and phone numbers. Names are words made of letters, so you use strings to keep them.

🎯 Goal: You will create a dictionary with names as strings and their phone numbers. Then you will check if a name is in the list and print a message.

📋 What You'll Learn

Create a dictionary called contacts with exact string keys and integer values

Create a variable called search_name with a string value

Use an if statement to check if search_name is in contacts

Print a message showing the phone number if found, or a not found message

💡 Why This Matters

🌍 Real World

Storing and searching names in contact lists, user databases, or any place where words identify data.

💼 Career

Understanding strings and dictionaries is essential for data handling in software development, customer management, and many programming tasks.

1

Create the contacts dictionary

Create a dictionary called contacts with these exact entries: 'Alice': 12345, 'Bob': 67890, 'Charlie': 54321

Python

# Create the contacts dictionary with names as strings and phone numbers as integers
# Your code here

Need a hint?

Use curly braces {} to create a dictionary. Names must be in quotes because they are strings.

2

Set the search name

Create a variable called search_name and set it to the string 'Bob'

Python

contacts = {'Alice': 12345, 'Bob': 67890, 'Charlie': 54321}
# Set the search_name variable to 'Bob'
# Your code here

Need a hint?

Remember to put the name in quotes because it is a string.

3

Check if the name is in contacts

Use an if statement to check if search_name is in contacts

Python

contacts = {'Alice': 12345, 'Bob': 67890, 'Charlie': 54321}
search_name = 'Bob'
# Use if statement to check if search_name is in contacts
# Your code here

Need a hint?

Use if search_name in contacts: to check presence. Access the phone number with contacts[search_name].

4

Print the result

Print "Bob's phone number is 67890" if search_name is in contacts, otherwise print "Bob is not in contacts"

Python

contacts = {'Alice': 12345, 'Bob': 67890, 'Charlie': 54321}
search_name = 'Bob'
if search_name in contacts:
    phone = contacts[search_name]
# Print the phone number or not found message
# Your code here

Need a hint?

Use an else block to print the not found message. Use f-strings to insert variables in the print.