code: def remove(self, peers):
          
          peers = set(peers)
          if not peers:
              return
          nheap = []
          for distance, node in self.heap:
              if node.id not in peers:
                  heapq.heappush(nheap, (distance, node))
          self.heap = nheap
docs: Remove a list of peer ids from this heap.  Note that while this
          heap retains a constant visible size (based on the iterator), it's
          actual size may be quite a bit larger than what's exposed.  Therefore,
          removal of nodes may not change the visible size as previously added
          nodes suddenly become visible.