The Task Bag is intended to be used by cooperating clients, some of which add pairs (describing tasks) and others of which remove them (and carry out the tasks described). When a client is informed that no matching pair is available, it cannot continue with its work until a pair becomes available. Define an appropriate callback interface for use in this situation.

What will be an ideal response?

This callback can send the value required by a readPair or pairIn operation. Its method should not be a oneway as the client depends on receiving it to continue its work.

```
interface TaskBagCallback{
void data(in Value value);
}
```