Multi-Producer Multi-Consumer Queue

Implement a multi-producer, multi-consumer priority queue in Python with following features.

• Each inserted item has a priority associated with it.

  • If the inserted item already exists in the queue, its new priority is the sum of the old and the new priority.
  • When extracting, items with the highest priority are returned first.

• Other functionality (e.g. blocking, safe concurrent operations of multiple threads, etc.) is similar to that of queue.Queue.

  • Ideally, it is possible to use PriorityQueue instead of queue.Queue at any place without modifications of the code.

• Implement method get_n(n: int, block: bool, timeout: Optional[float]) -> List[Item] batching the results.

  • Queue blocks until at least n items are available (or timeout expires) and then return the gathered items.