Laravel Eloquent Query Using WHERE with OR AND OR (orWhere)

 Model::where(function ($query) use ($a,$b) {

    $query->where('a', '=', $a)
          ->orWhere('b', '=', $b);
})

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if (isset($_GET["ids"])) {
            $ids = $_GET["ids"];
            $id_list = explode(",", $ids);
            $notes = Note::where(function ($query) use ($id_list) {
                $query->where(true);
                foreach ($id_list as &$id) {
                    $query->orWhere('id', $id);
                }
            });
            $notes = $notes->get();
            return response()->json($notes);
        }