code: func (deque *keyedDeque) Clear() {
  	deque.Lock()
  	defer deque.Unlock()
  
  	deque.syncedList.Clear()
  	deque.index = make(map[interface{}]*list.Element)
  	deque.invertedIndex = make(map[*list.Element]interface{})
  }
docs: // Clear resets the deque.