interface Crud 
{
    public function create($data);
    public function read();
    public function update($data);
    public function delete();
}

class User implements Crud 
{
    /* ... */
    
    function create($data)   { /* ... */ }
    function read()          { /* ... */ }
    function update($data)   { /* ... */ }
    public function delete() { /* ... */ }
}