Question

Favorite Book: Write a function called favorite_book() that accepts one parameter, title. The function should print a message, such as One of my favorite books is Alice in Wonderland. Call the function, making sure to include a book title as an argument in the function call.

Short answer

Define a function with a title parameter, print the message, then call the function with a book title.

Step-by-step solution

Define the Function

Start by defining a function named `favorite_book`. This function should take one parameter, which we'll call `title`. This parameter will be used to pass the name of the book into the function.

Create the Message

Inside the function, construct a message string that includes the parameter `title`. For example, the message could be 'One of my favorite books is ' followed by the book title.

Print the Message

Use the `print` function to output the message. This will display the message to the user whenever the function is called.

Call the Function

Outside of the function, call `favorite_book` and pass a book title as an argument, such as 'Alice in Wonderland'. This will trigger the function to execute and print the message with the specified book title.

Key concepts

Function Parameters

When writing functions in Python, it's often necessary to use parameters to make them more flexible and robust. Parameters are special variables that allow us to pass information into a function.
In the case of our `favorite_book` function, the parameter is `title`. This is a placeholder for any book name we want to work with. Parameters enable functions to be reused with different inputs, which is a cornerstone of efficient coding. Once we define the function with its parameters, we can use these values inside the function to perform various operations, like message construction or calculations.
Consider a parameter as a "catching bucket" that waits for a specific value when the function is called. For example:

• Define a function: `def favorite_book(title):`
• Here, `title` is the parameter that's waiting to receive a book name.

This makes the function highly adaptable because you can pass any book title you like when you call the function.

Message Construction

Constructing messages inside functions is a powerful way to make your output dynamic and personalized. In our `favorite_book` function, we create a message that includes the book title provided through the parameter.
To do this, we combine static text with the variable `title` to form a complete sentence. You can think of this as building a phrase with both fixed and variable parts:

• The static part: "One of my favorite books is "
• The dynamic part: Whatever `title` is passed when the function is called

By using concatenation, which is the process of joining strings, we can create custom messages easily. In Python, you can concatenate strings using the `+` operator: ```python message = 'One of my favorite books is ' + title ``` This line of code constructs an individualized message based on the provided book title. This makes your programs much more engaging, as they provide specific feedback or information tailored to the input provided.

Function Calls

Calling a function is the process of executing the function with a specific set of values or arguments. It's at this point that function parameters get their values. In our example, the function call looks like: ```python favorite_book('Alice in Wonderland') ``` Here, the function `favorite_book` is called, and the argument `'Alice in Wonderland'` is passed to the `title` parameter. This triggers the function to execute its code block, which constructs and prints the message.
A function call can be thought of as "activating" the function. You can call a function as many times as needed, and each call can pass different arguments. This flexibility is incredibly useful in programming, as it allows for code reusability and modularity.
Additionally, properly calling a function ensures that the program behaves as expected, providing correct output based on the input. Always remember to double-check the arguments you pass in function calls to ensure they match the expected parameter types and values.