Expanding the User Class with Instance Methods

Until now, we’ve had users post chirps manually by creating Post objects and passing the user as an argument. But as our project grows, we begin to realize that it would be far more efficient and intuitive if users could create posts directly without having to construct Post objects manually every time.

This is where the relationship between a class and its objects becomes essential. A class is like a blueprint—it defines the structure and behavior (methods) that all its objects (instances) will have. When you create an object from a class, it inherits all the defined behaviors and properties. In object-oriented programming, methods are functions defined within a class that act on the object’s data using the self parameter. By tying functionality like create_post() to the User class as an instance method, we enable each user object to “do something” on its own—such as creating posts or liking posts—without needing to manually assemble Post objects outside of the user’s context. This design not only simplifies our code but also reinforces the core OOP principle that an object is a bundle of data and behavior.

Now, we’ll enhance our User class by adding instance methods that let a user create posts and even like posts directly. This change streamlines our code and reinforces the natural connection between an object and the actions it can perform.

Why instance methods?

Before we dive into the implementation, ask yourself:

How do you usually tell an object to do something?

In our project, a user should be able to create a post without having to manually call the Post class every time. Instance methods let us do just that!

• Instance methods are functions that are defined inside a class and are called on objects. They have access to the instance’s data via the self parameter.

Adding create_post() to the user class

We’ll add a create_post() method inside our User class. This method will construct a new Post object automatically, linking the post to the user who created it. But before creating it, let’s visualize how it actually works.