We're going to make a very minimal favorite things list. We want to store favorite numbers and favorite people with their favorite numbers. Here is some basic code to get started: ```python # favorite things list: # favorite numbers # favorite people with their favorite number ``` To store these items, we're going to use mappings. A mapping is like a dictionary or hashmap. We'll use the key to be the person and the value to be their favorite number. ```python # favorite things list: # favorite numbers # favorite people with their favorite number favorite_numbers: dict[uint256, uint256] favorite_people: dict[address, uint256] ``` Mappings have a default value. If we don't assign a value, the default value is 0. ```python # favorite things list: # favorite numbers # favorite people with their favorite number favorite_numbers: dict[uint256, uint256] favorite_people: dict[address, uint256] def set_favorite_number(number: uint256): favorite_numbers[number] = number ``` Now we have a function to set a favorite number. This is a pretty simple and straightforward function. We take a number and set it to the same number, but we could change this later. ```python # favorite things list: # favorite numbers # favorite people with their favorite number favorite_numbers: dict[uint256, uint256] favorite_people: dict[address, uint256] def set_favorite_number(number: uint256): favorite_numbers[number] = number def set_favorite_person(person: address, number: uint256): favorite_people[person] = number ``` We have another function to set the favorite person. It takes a person, their address, and their favorite number. We set it to the dictionary where we store the favorite person. ```python # favorite things list: # favorite numbers # favorite people with their favorite number favorite_numbers: dict[uint256, uint256] favorite_people: dict[address, uint256] def set_favorite_number(number: uint256): favorite_numbers[number] = number def set_favorite_person(person: address, number: uint256): favorite_people[person] = number def get_favorite_number(number: uint256) -> uint256: return favorite_numbers[number] ``` Lastly, we have a function to get the favorite number. It takes a number and then it returns the favorite number. It simply returns the value of the number from the dictionary. ```python # favorite things list: # favorite numbers # favorite people with their favorite number favorite_numbers: dict[uint256, uint256] favorite_people: dict[address, uint256] def set_favorite_number(number: uint256): favorite_numbers[number] = number def set_favorite_person(person: address, number: uint256): favorite_people[person] = number def get_favorite_number(number: uint256) -> uint256: return favorite_numbers[number] def get_favorite_person(person: address) -> uint256: return favorite_people[person] ``` We now have a function to get the favorite person, which takes a person's address and returns their favorite number.