code: func (sc *shardedCache) Items() []map[string]Item {
  	res := make([]map[string]Item, len(sc.cs))
  	for i, v := range sc.cs {
  		res[i] = v.Items()
  	}
  	return res
  }
docs: // Returns the items in the cache. This may include items that have expired,
  // but have not yet been cleaned up. If this is significant, the Expiration
  // fields of the items should be checked. Note that explicit synchronization
  // is needed to use a cache and its corresponding Items() return values at
  // the same time, as the maps are shared.