How can I load non-related model as relationship ?

Hello all. I have a User and Lesson models. these models are not related to each other.

users table: id, username, password, is_active lessons table: id, title

User
class User extends Modle
{
    // code 
}

Lesson
class Lessosn extends Modle
{
    public function users()
    {
        // I need to return all users here where is_active=true as RELATIONSHIP
        // return User::where('is_active', true);
    }
}

In the Lesson model I want to have a relationship to load users where (is_active, true) So I can list all users where is_active = true

Thanks