How can PHP classes be structured to avoid including source files that belong to the same project?

When structuring PHP classes, it's important to organize your source files in a way that avoids including files that belong to the same project multiple times. This can be achieved by using namespaces to group related classes and files together, ensuring that each file only includes the necessary classes from external sources. By following this practice, you can prevent conflicts and improve the overall organization of your project.

// File: MyClass.php
namespace MyProject;

class MyClass {
    // Class implementation
}
```

```php
// File: AnotherClass.php
namespace MyProject;

class AnotherClass {
    // Class implementation
}