```dart
import 'package:amplify_flutter/amplify_flutter.dart';

import 'models/ModelProvider.dart';

Future<void> savePredicate(Post post) async {
  final post = ...; // get post using the query API
  final updatedPost = post.copyWith(title: '[Amplified]');
  try {
    // if the post title has changed to something else other than
    // a string that starts with "[Amplify]", the save will be rejected
    await Amplify.DataStore.save(
      updatedPost,
      where: Post.TITLE.beginsWith("[Amplify]"),
    );
  } on DataStoreException {
    safePrint('Could not update post, maybe the title has been changed?');
  }
}
```