Project: Contact Book

A contact book is a natural fit for dictionaries: each contact has a name (the key) and a small record of details (the value). You will build one that stores contacts, adds a new one, and prints them in order.

What You'll Build

Step 1: A Dictionary of Records

Each contact's value is itself a small dictionary. This nesting keeps related details together:

Step 2: Add a Contact

Adding is just assigning a new key:

Step 3: List Them in Order

sorted(contacts) gives the names alphabetically. Loop over them and pull each phone number out of the record.

Build It Yourself

Reproduce the exact output below.

Make It Your Own

Look up a single contact safely with get() so a missing name does not crash your program:

Challenge Ideas

• Add a delete feature with del contacts[name]
• Search for contacts whose name starts with a given letter
• Print the email as well as the phone for each contact

Key Takeaways

• Model records as a dictionary of dictionaries
• Add a contact by assigning a new key
• sorted(dict) iterates keys in order
• get() looks up a contact without risking an error
• This is the core of any address book or CRM