Rank 3: Container
is this will be worked as batch delete ? ```dart
class FutureGroup {
final List<Completer> _completers = [];
final int maxConcurrent;
FutureGroup({this.maxConcurrent = 1});
Future add(Future future) async {
if (_completers.length >= maxConcurrent) {
await Future.any(_completers.map((c) => c.future));
}
final completer = Completer<T>();
_completers.add(completer);
future.whenComplete(() => _completers.remove(completer));
return completer.complete(await future);
}
Future close() => Future.wait(_completers.map((c) => c.future));
}
Future deleteDocumentsConcurrently(List documentIds) async {
final batchFutures = FutureGroup(maxConcurrent: 100);
for (final documentId in documentIds) {
await batchFutures.add(database.deleteDocument(
databaseId: "6439e7ae4abb3e14f2b1",
collectionId: "64444e34a0ce20bc4ac8",
documentId: documentId,
));
}
await batchFutures.close();
print('All documents deleted');
}````