code: func Table(table string) *RegommendTable {
  	mutex.RLock()
  	t, ok := tables[table]
  	mutex.RUnlock()
  
  	if !ok {
  		t = &RegommendTable{
  			name:  table,
  			items: make(map[interface{}]*RegommendItem),
  		}
  
  		mutex.Lock()
  		tables[table] = t
  		mutex.Unlock()
  	}
  
  	return t
  }
docs: // Table returns the existing engine table with given name or creates a new one
  // if the table does not exist yet.