code: def _clear(self):
          '''
          Actual clear
          '''
          ret = ([],[])
          for q in self.queues.values():
              pr = q._clear()
              ret[0].extend(pr[0])
              ret[1].extend(pr[1])
          self.totalSize = 0
          del self.prioritySet[:]
          if self.isWaited and self.canAppend():
              self.isWaited = False
              ret[0].append(QueueCanWriteEvent(self))
          if self.isWaitEmpty and not self:
              self.isWaitEmpty = False
              ret[1].append(QueueIsEmptyEvent(self))
          self.blockEvents.clear()
          return ref _clear(self):
          '''
          Actual clear
          '''
          ret = ([],[])
          for q in self.queues.values():
              pr = q._clear()
              ret[0].extend(pr[0])
              ret[1].extend(pr[1])
          self.totalSize = 0
          del self.prioritySet[:]
          if self.isWaited and self.canAppend():
              self.isWaited = False
              ret[0].append(QueueCanWriteEvent(self))
          if self.isWaitEmpty and not self:
              self.isWaitEmpty = False
              ret[1].append(QueueIsEmptyEvent(self))
          self.blockEvents.clear()
          return ret
docs: Actual clear