This is the Python version of the PhoneBook lab for beginner coders.

• Python 3.7 or higher

To run all tests:

python -m unittest discover -s . -p "test_*.py"

To run a specific test file:

python -m unittest test_constructor.py

Students need to implement the following methods in phonebook.py:

1. __init__() - Constructor that initializes the phonebook dictionary
2. add() - Add a phone number for a contact
3. add_all() - Add multiple phone numbers for a contact
4. remove() - Remove a contact from the phonebook
5. has_entry() - Check if a contact exists (with optional phone number check)
6. lookup() - Look up all phone numbers for a contact
7. reverse_lookup() - Find the contact name for a given phone number
8. get_all_contact_names() - Get all contact names in the phonebook
9. get_map() - Get the underlying dictionary representation

• test_constructor.py - Tests for constructor functionality
• test_add_all.py - Tests for adding multiple phone numbers
• test_get_all_contact_names.py - Tests for retrieving all contact names
• test_remove.py - Tests for removing contacts
• test_reverse_lookup.py - Tests for reverse phone number lookup

The phonebook uses a dictionary where:

• Keys are contact names (strings)
• Values are lists of phone numbers (List[str])

Example:

{
    "John": ["302-555-1234", "302-555-5678"],
    "Jane": ["302-555-9999"]
}