# Example 04: Context Interaction (Computed Properties)

Models in Typedown aren't just data containers; they are standard Python classes. You can add methods and properties to them. These computed properties can then be used in your specs.

## Concepts

1.  **`@property`**: Define computed fields in your Model.
2.  **Code Reuse**: Complex logic can be encapsulated in the Model, making Specs cleaner.

## How to Run

```bash
td check --path examples/04_context_interaction
```
